Resilient knee implant and methods

ABSTRACT

This disclosure is directed to a resilient interpositional arthroplasty implant for application into a joint to pad cartilage defects, cushion, and replace or restore the articular surface, which may preserve joint integrity, reduce pain and improve function. The implant may endure variable joint compressive and shear forces and cyclic loads. The implant may repair, reconstruct, and regenerate joint anatomy, and thereby improve upon joint replacement alternatives. The walls of this invention may capture, distribute and hold living cells until aggregation and hyaline cartilage regrowth occurs. The implant may be deployed into debrided joint spaces, molding and conforming to surrounding structures with sufficient stability so as to enable immediate limb use after outpatient surgery. Appendages of the implant may repair or reconstruct tendons or ligaments, and menisci by interpositional compliant polymer arthroplasties that promote anatomic joint motion.

RELATED APPLICATIONS

This application is a continuation in part of and claims priority toU.S. application Ser. No. 15/608,885 filed on May 30, 2017 which is adivisional of U.S. application Ser. No. 14/289,431 filed on May 28, 2014now U.S. Pat. No. 9,662,218 which is a continuation of U.S. applicationSer. No. 13/574,499 filed Oct. 8, 2012 now U.S. Pat. No. 8,771,363 whichis the is National Stage Entry of PCT/US2011/021674 filed Jan. 19, 2011,which claims priority to Provisional U.S. Application Ser. No.61/297,698 filed Jan. 22, 2010, the entire contents of which areincorporated herein by reference in their entirety for any purpose.

This application is a continuation in part of and claims priority tocurrently pending U.S. application Ser. No. 15/651,958 filed on Jul. 17,2017, which is a continuation of U.S. application Ser. No. 14/239,992filed on Jun. 5, 2014 now U.S. Pat. No. 9,757,241 which is the NationalStage Entry of PCT/US2012/053207 filed on Aug. 30, 2012, which claimspriority to Provisional U.S. Application Ser. No. 61/530,324 filed onSep. 1, 2011, the entire contents of which are incorporated herein byreference in their entirety for any purpose.

This application claims the benefit of provisional U.S. Application Ser.No. 62/577,071 filed on Oct. 25, 2017.

BACKGROUND OF THE INVENTION

This invention relates to arthroplasty, and more particularly, to animplant for use in arthroplasty when hyaline articular cartilage isdamaged, it breaks down and joint space is lost. Inflammatory enzymessuch as from the Cox-1, Cox-2 and/or 5-Lox systems, are released andloose bodies form adding to the degradation of joint function. Suchjoint damage is conventionally treated by physical therapy, analgesics,pain medication and injections. When these treatments fail, thetraditionally accepted treatment option is arthroplasty implantation orreplacing the joint with an artificial joint construct. Currentarthroplasty techniques typically use “plastic and metal” implants thatare rigid and which ultimately fail due to loosening or infection.Conventional materials for the artificial joint components includechrome-cobalt-molybdenum alloy (metal) and high molecular weightpolyethylene (plastic). Each is often fixed by a cement-like mixture ofmethyl methacrylate to the ends of the bones that define the joint thatis the subject of the arthroplasty, or coated with a surface thatenables bone ingrowth. Replacement surgeries are known to fail in anumber of years.

Conditions requiring arthroplasty include traumatic arthritis,osteoarthritis, rheumatoid arthritis, osteonecrosis, and failed surgicalprocedures.

SUMMARY OF THE INVENTION

The present invention is directed to an orthopedic implant configuredfor deployment between opposing members of a joint structure thataddresses many of the shortcomings of prior artificial joints. Thearthroplasty implants embodying features of the invention are configuredto preserve joint motions while removing the pain and dysfunctionfollowing the development of arthritis or joint injury. The arthroplastyimplant in accordance with the present invention achieves improvedphysiologic motion and shock absorption during gait and acts as aresilient spacer between moving bones during limb movement. The combinedcharacteristics of the implant include anatomic design symmetry,balanced rigidity with variable attachment connections to at least oneof adjacent normal structures, and durability which addresses and meetsthe needs for repair or reconstruction thus far missed in the prior art.The implant should be secured to at least one of the bones of the jointstructure.

Provided herein is an implant configured for deployment between a femurand a tibia of a knee joint, the implant comprising a balloon comprisinga first portion that is configured to engage a medial condyle and alateral condyle of the femur of the knee joint, a second portion that isconfigured to engage the tibia of the knee joint, a side portionconnecting the first portion and the second portion, in which the sideportion facilitates relative motion between the first portion and thesecond portion, and an interior that is optionally inflatable with afirst inflation medium; and a first appendage configured to couple theballoon to the femur of the knee joint.

In some embodiments, the implant comprises at least one attachmentelement in the intercondylar notch. In some embodiments, the implantcomprises at least one attachment element superiorly at the distal endof the femur anteriorly. In some embodiments, the implant comprises atleast one posterior reign configured to cinch up the implant from insidea posterior intercondylar notch toward a connection site around thefemur. In some embodiments, the implant comprises at least onesuture-like lanyard configured to cinch up the implant from inside aposterior intercondylar notch toward a connection site around the femur.

In some embodiments, the first portion comprises a first wall, thesecond portion comprises a second wall, and the side portion comprises aside wall.

In some embodiments, the implant is a single layer or monolayer ofpolymer. In some embodiments, the implant does not have a balloon orinflatable portion thereof. In other embodiments the implant is amultilayered structure, a laminate or a coextruded multilayered device.

In one embodiment, the implant is configured for a knee joint and theimplant comprises a first appendage that is configured to engage amedial condyle of a femur of a knee joint, the first appendagecomprising a bone engaging surface and an articulating surface, a secondappendage that is configured to engage a lateral condyle of a femur of aknee joint, the second appendage comprising a bone engaging surface andan articulating surface, a slot between the first appendage and thesecond appendage, and a rim defining the periphery of the implant,wherein the bone engaging surface of the first appendage has a similarradial curvature profile as the articulating surface of the firstappendage. In another embodiment, the first and second appendage arepart of the same implant. In still another embodiment, the first andsecond appendage are seamlessly part of the same implant and arecoextensively juxtaposed. In yet another embodiment the first and secondappendage coextensively share a common third appendage.

In another embodiment, the implant may have prefabricated holes foraiding in the attachment of the implant to a bone. The implant may, insome aspects, have a variable thickness or a consistent thicknessdepending on the needs of the subject receiving the implant. In apreferred embodiment, the implant has an average thickness. In someembodiments, the implant thickness is as thin as possible given thematerials used to fabricate the implant so that the implant fits thesubject and allows for an improved joint function. Preferably, thethickness of the implant of is from 0.05 to 5 mm. More preferably, theaverage thickness of the implant of is from 0.05 to 5 mm.

In other aspects, the implant has a rim which defines the periphery ofthe implant. The rim may be filleted. The filleted rim may have avariable fillet. In some embodiments, prefabricated holes may be made inthe rim. In some aspects, the dimensions of the rim are relative to thethickness of the rest of the implant. In other aspects, the rim can havea peripheral boundary and an inner boundary wherein the inner boundaryis conterminous or coextensive with the main body or appendages of theimplant. In preferred aspects, the rim can have a dimension that is 1 to3.5 times the thickness of the implant.

In some embodiments, the implant can be implanted without removing ordamaging a patient's ligaments or other cooperating bones such as thepatella. Therefore, in certain aspects, the implant will functionrelative to, in cooperation with or in apposition to other parts of theknee joint that were present in the patient prior to implanting of theimplant. In a preferred aspect, the implant is implanted while keepingthe remainder of the patient's joint intact. In a preferred aspect, theimplant is implanted without cutting or damaging any ligaments. In apreferred aspect, the implant is implanted without removing any bone. Insome embodiments, the implant comprises an inflation port incommunication with the interior of the balloon for inflation of theinterior of the balloon with the first inflation medium. In someembodiments, the interior comprises a plurality of inflatable chambers.In some embodiments, a first chamber of the plurality of individuallyinflatable chambers is adapted to be inflated with the first inflationmedium, and a second chamber of the plurality of individually inflatablechambers is adapted to be inflated with a second inflation medium. Insome embodiments, the first inflation medium imparts at least one ofrigidity in the implant and cushion in the implant.

In some embodiments, the implant comprises a second appendage couplingthe balloon to at least one of: the femur of the joint and the tibia ofthe joint.

Provided herein is an implant configured for deployment between a femurand a tibia of a knee joint, the implant comprising a balloon comprisinga first portion that is configured to engage at least one condyle of thefemur of the knee joint, a second portion that is configured to engagethe tibia of the knee joint, a side portion connecting the first portionand the second portion, in which the side portion facilitates relativemotion between the first portion and the second portion, and an interiorthat is optionally inflatable with a first inflation medium; and a firstappendage configured to couple the balloon to the femur of the kneejoint.

In some embodiments, the at least one condyle is the medial condyle. Insome embodiments, the at least one condyle is the lateral condyle.

In some embodiments, the balloon is at least one of: at most about 1.5cm in diameter, at most about 1.75 cm in diameter, at most about 2 cm indiameter, at most about 2.25 cm in diameter, at most about 2.5 cm indiameter, at most about 2.75 cm in diameter, at most about 3 cm indiameter, at most about 3.25 cm in diameter, at most about 3.5 cm indiameter, at most about 3.75 cm in diameter, at most about 4 cm indiameter, at most about 4.25 cm in diameter, at most about 4.5 cm indiameter, at most about 4.75 cm in diameter, at most about 5 cm indiameter, at most about 5.25 cm in diameter, at most about 5.5 cm indiameter, at most about 5.75 cm in diameter, at most about 6 cm indiameter, at most about 6.25 cm in diameter, at most about 6.5 cm indiameter, at most about 6.75 cm in diameter, at most about 7 cm indiameter, at most about 7.25 cm in diameter, at most about 7.5 cm indiameter, at most about 7.75 cm in diameter, at most about 8 cm indiameter, at most about 3 cm in length along the longest length of theballoon, at most about 3.25 cm in length along the longest length of theballoon, at most about 3.5 cm in length along the longest length of theballoon, at most about 3.75 cm in length along the longest length of theballoon, at most about 4 cm in length along the longest length of theballoon, at most about 4.25 cm in length along the longest length of theballoon, at most about 4.5 cm in length along the longest length of theballoon, at most about 4.75 cm in length along the longest length of theballoon, at most about 5 cm in length along the longest length of theballoon, at most about 5.25 cm in length along the longest length of theballoon, at most about 5.5 cm in length along the longest length of theballoon, at most about 5.75 cm in length along the longest length of theballoon, at most about 6 cm in length along the longest length of theballoon, 6.25 cm in length along the longest length of the balloon, atmost about 6.5 cm in length along the longest length of the balloon, atmost about 6.75 cm in length along the longest length of the balloon, atmost about 7 cm in length along the longest length of the balloon, atmost about 7.25 cm in length along the longest length of the balloon, atmost about 7.5 cm in length along the longest length of the balloon, atmost about 7.75 cm in length along the longest length of the balloon,and at most about 8 cm in length along the longest length of theballoon.

In some embodiments, the first portion comprises a first wall, thesecond portion comprises a second wall, and the side portion comprises aside wall.

In some embodiments, the implant comprises an inflation port incommunication with the interior of the balloon for inflation of theinterior of the balloon with the first inflation medium. In someembodiments, the interior comprises a plurality of inflatable chambers.In some embodiments, a first chamber of the plurality of individuallyinflatable chambers is adapted to be inflated with the first inflationmedium, and a second chamber of the plurality of individually inflatablechambers is adapted to be inflated with a second inflation medium. Insome embodiments, the first inflation medium imparts at least one ofrigidity in the implant and cushion in the implant.

In some embodiments, the implant comprises a second appendage couplingthe balloon to at least one of: the femur of the joint and the tibia ofthe joint. In some embodiments, the implant comprises at least oneattachment element in the intercondylar notch. The In some embodiments,the implant comprises at least one attachment element superiorly at thedistal end of the femur anteriorly. In some embodiments, the implantcomprises at least one posterior reign configured to cinch up theimplant from inside a posterior intercondylar notch toward a connectionsite around the femur. In some embodiments, the implant comprises atleast one suture-like lanyard configured to cinch up the implant frominside a posterior intercondylar notch toward a connection site aroundthe femur.

In some embodiments, the implant is manufactured as a multilayerstructure or laminate, such as a coextruded laminate. In a preferredembodiment, the implant is a single layer or monolayer of polymer. Inother embodiments, the implant does not have a balloon or inflatableportion thereof. Whether the implant is a monolayer or multilayerstructure, the layers can be made of for example, BIONATE® (e.g.,BIONATE® I, BIONATE® II, BIONATE® 55D, BIONATE® 65D, BIONATE® 75D,BIONATE® 80, BIONATE® 80A, BIONATE® 90A) or one or more layers ofChronoflex (e.g., ChronoFlexAR®, ChronoFlex AL®, ChronoFlec C®).

Provided herein is an implant configured for patch a defect of a bone ofa knee joint, the implant comprising a balloon configured to engage thedefect of the bone of the knee joint and comprising an interior that isoptionally inflatable with a first inflation medium; and a firstappendage configured to couple the balloon to the bone of the kneejoint.

In some embodiments, at least one of the appendage and the balloon areconfigured to replace cartilage.

In some embodiments, the balloon is at least one of: at most about 0.5cm in diameter, at most about 0.75 cm in diameter, at most about 1 cm indiameter, at most about 1.25 cm in diameter, at most about 1.5 cm indiameter, at most about 1.75 cm in diameter, at most about 2 cm indiameter, at most about 2.25 cm in diameter, at most about 2.5 cm indiameter, at most about 2.75 cm in diameter, at most about 3 cm indiameter, at most about 3.25 cm in diameter, at most about 3.5 cm indiameter, at most about 3.75 cm in diameter, at most about 0.5 cm inlength along the longest length of the balloon, at most about 0.75 cm inlength along the longest length of the balloon, at most about 1 cm inlength along the longest length of the balloon, at most about 1.25 cm inlength along the longest length of the balloon, at most about 1.5 cm inlength along the longest length of the balloon, at most about 1.75 cm inlength along the longest length of the balloon, at most about 2 cm inlength along the longest length of the balloon, at most about 2.25 cm inlength along the longest length of the balloon, at most about 2.5 cm inlength along the longest length of the balloon, at most about 2.75 cm inlength along the longest length of the balloon, at most about 3 cm inlength along the longest length of the balloon, at most about 3.25 cm inlength along the longest length of the balloon, at most about 3.5 cm inlength along the longest length of the balloon, at most about 3.75 cm inlength along the longest length of the balloon, and at most about 4 cmin length along the longest length of the balloon.

In some embodiments, the size of the balloon size is pre-set. In someembodiments, the balloon comprises multiple chambers which may beselectively inflated. In some embodiments, the balloon comprisesmultiple chambers which may be selectively deflated. In someembodiments, the balloon comprises multiple chambers which may beselectively inflated in situ to fill the defect. In some embodiments,the balloon comprises multiple chambers which may be selectivelyinflated just prior to implantation.

In some embodiments, the balloon or a chamber thereof may be secondarilyinflated, deflated, or a combination thereof in situ.

In some embodiments, the implant comprises an ingrowth matrix on atleast a portion of the implant adjacent the femur. In some embodiments,the ingrowth matrix comprises living chondrocytes. In some embodiments,the implant is configured to release the chondrocytes over time. In someembodiments, the implant comprises a bioabsorbable polymer configured torelease the chondrocytes over time. In some embodiments, the implantcomprises a polymer configured to release the chondrocytes over time,wherein the polymer is not bioabsorbable. In some embodiments, theingrowth matrix comprises at least one of: autologous cells, allographcells, and xenograph cells to restore an articular surface of the femur.In some embodiments, the ingrowth matrix comprises at least one of:autologous cells, allograph cells, and xenograph cells to repair anarticular surface of the femur.

In some embodiments, the implant comprises couplers that couple theappendage to the femur. In some embodiments, the coupler isbioabsorbable. In some embodiments, the coupler is at least one of: ascrew, a washer, a suture, a suture anchor, a rivot, a staple, a staplehaving teeth, a stabilizer, a glue, a hook, a wire, a string, a lasso, alanyard, a spike, and combinations thereof. The implant may also and/oralternatively be attached via bone ingrowth.

In some embodiments, the implant comprises a phamacologic agent. In someembodiments, the pharmacologic agent is on a surface of the implantadjacent the femur. In some embodiments, the pharmacologic agent isreleased from the implant over time. In some embodiments, thepharmacologic agent is released from within the implant over time. Insome embodiments, the pharmacologic agent is released from within theballoon over time.

In some embodiments, the inflation medium is compressible. In someembodiments, the inflation medium comprises a viscolubricant. In someembodiments, the inflation medium comprises an NSAID. In someembodiments, the inflation medium comprises chondrocytes.

In some embodiments, at least a portion of the implant is configured toanneal to a periphery of a cartilage defect.

In some embodiments, the implant comprises vacuoles of pharmacologicsubstances. In some embodiments, the vacuoles may be on a bone-engagingportion of the implant. In some embodiments, the implant comprisesbubbles comprising an active substance such as a pharmacologic substanceor other active agent. In some embodiments, the active agent comprisesat least one of: stem cells, growth factors, antibiotics, andviscolubricants. In some embodiments, the active agent comprisesiatrigenically gene mutated cells.

In some embodiments, the implant comprises enzyme absorptive microscopicsponges that could be sucked out or evacuated at or around the time ofimplant delivery to the joint.

In some embodiments, the implant comprises spaces filled with an activesubstance such as a pharmacologic substance or other active substance.In some embodiments, the implant is configured to deliver by dissolutionof the implant material In some embodiments, the implant is configuredto deliver by release through pores of the implant. In some embodiments,the implant is configured to deliver by fracture of a vacuole by acatalyst such as ultrasound or pressure or other fracturing catalyst.

In some embodiments, the implant is configured to at least one of: padcartilage, cushion the joint, deliver a pharmacologic substance, removenoxious enzymes, debride upon implantation, debride the joint followingimplantation, deliver a therapeutic substance, deliver a biologicsubstance, and deliver living stem cells. In some embodiments, theimplant is configured to deliver a chemotherapeutic agent to a bone orother surrounding tissues. In some embodiments, the implant isconfigured to deliver an anti-infectious medication to a bone or othersurrounding tissues. In some embodiments, the implant is configured todeliver at least one of an antibiotic, antifungals, and analgesicsagent.

In some embodiments, the implant is configured to be selectivelyinflated to realign limbs.

Provided herein is a method comprising: implanting a knee implant asdescribed herein into a subject, wherein the implant reverses arthritisin the subject.

Provided herein is a method comprising: implanting a knee implant asdescribed herein into a knee joint of a subject and treating a componentof the knee joint of the subject with at least one of an allographtissue, an autograph tissue, and an xenograph tissue. In someembodiments, the implanting step is at least one of: prior to thetreating step, simultaneous with the treating step, and following thetreating step.

Provided herein is a method comprising: implanting a knee implant asdescribed herein into a subject, wherein the implant at least one of:restores joint function and controls arthopathies. In some embodiments,the implanting spares existing anatomy.

Provided herein is a method comprising: debriding a femur condyle of aknee joint of a subject, and implanting a knee implant as describedherein into the knee joint of the subject, whereby the implant isconfigured to anneal to the cartilage of the subject. In someembodiments, the debriding is achieved by steam application.

Provided herein is a method comprising implanting a knee implant asdescribed herein into a joint previously treated with a jointreplacement. In some embodiments, the method comprises removing thejoint replacement prior to implanting the knee implant. In someembodiments, the method comprises clearing infectious matter from thejoint and/or surrounding tissues. In some embodiments, the methodcomprises implanting a second implant of any implant described hereinfollowing removing the implant previously implanted in the joint. Insome embodiments, the method comprises replacing the joint of thesubject following removing the implant previously implanted in thejoint. In some embodiments, the method comprises debriding the bone ofthe joint, and implanting an implant of any implant described herein. Insome embodiments, the method comprises repeating the debriding andimplanting steps.

These and other advantages of the invention will become more apparentfrom the following detailed description and the attached exemplarydrawings.

INCORPORATION BY REFERENCE

All publications, patents, and patent applications mentioned in thisspecification are herein incorporated by reference to the same extent asif each individual publication, patent, or patent application wasspecifically and individually indicated to be incorporated by reference.

BRIEF DESCRIPTION OF THE DRAWINGS

The novel features of the invention are set forth with particularity inthe appended claims. A better understanding of the features andadvantages of the present invention will be obtained by reference to thefollowing detailed description that sets forth illustrative embodiments,in which the principles of the invention are utilized, and theaccompanying drawings of which:

FIG. 1 depicts an embodiment of the knee implant having appendagesincluding holes and tabs extending from a balloon and including slots toaccommodate ligaments of the knee joint.

FIG. 2 depicts an embodiment of the knee implant having appendagesincluding holes and tabs extending from a balloon and including slots toaccommodate ligaments of the knee joint as well as side views of thesame knee implant.

FIG. 3 depicts an embodiment of the knee implant having appendagesincluding holes and tabs extending from a balloon and including slots toaccommodate ligaments of the knee joint as well as side views of thesame knee implant.

FIG. 4A depicts an embodiment of the knee implant having appendagesincluding ten tabs extending from a balloon and including a slot toaccommodate components of the knee joint.

FIG. 4B depicts an embodiment of the knee implant having appendagesincluding eight tabs extending from a balloon and including a slot toaccommodate components of the knee joint.

FIG. 5 depicts an embodiment of the knee implant curved to simulatecurvature about the condyles of a femur, the implant having appendagesextending from an uninflated balloon (not shown) and including slots toaccommodate ligaments of the knee joint.

FIG. 6A depicts a top-down view of an embodiment of the knee implantcurved to simulate curvature about the condyles of a femur, the implanthaving appendages extending from two inflated balloons and includingslots to accommodate components of the knee joint.

FIG. 6B depicts a bottom-up view of an embodiment of the knee implantcurved to simulate curvature about the condyles of a femur, the implanthaving appendages extending from two inflated balloons and includingslots to accommodate components of the knee joint.

FIG. 7 depicts a top-down view of an embodiment of the knee implantcurved to simulate curvature about the condyles of a femur, the implanthaving appendages extending from an inflated balloon and including slotsto accommodate components of the knee joint.

FIG. 8 depicts a side view of an embodiment of the knee implant curvedto simulate curvature about at least one condyle of a femur, the implanthaving appendages extending from an uninflated balloon (not shown).

FIG. 9A depicts a side view of an embodiment of the knee implant curvedabout at least one condyle of a femur, the implant having appendagesextending from an uninflated or minimally inflated balloon.

FIG. 9B depicts a side view of an embodiment of the knee implant curvedabout at least one condyle of a femur, the implant having appendagesextending from an inflated balloon.

FIG. 9C depicts a side view of an embodiment of the knee implant curvedabout at least one condyle of a femur, the implant having appendagesextending from an inflated balloon and having staples or screws couplingthe appendages to the femur.

FIG. 10A depicts a side view of an embodiment of the knee implant curvedabout at least one condyle of a femur, the implant having appendagesextending from an inflated balloon and showing the inflation mediummoved anteriorly toward the patella when the knee joint is flexed.

FIG. 10B depicts a side view of an embodiment of the knee implant curvedabout at least one condyle of a femur, the implant having appendagesextending from an inflated balloon and having staples or screws couplingthe appendages to the femur and showing the inflation medium movedanteriorly toward the patella when the knee joint is flexed.

FIG. 11A depicts an embodiment of the unicompartment knee implant curvedto simulate curvature about one condyle of a femur, the implant havingappendages extending from an uninflated balloon (not shown) andincluding tabs and holes which may be used with couplers to couple theimplant to the femur of the knee joint.

FIG. 11B depicts an embodiment of the unicompartment knee implant curvedto simulate curvature about one condyle of a femur, the implant havingappendages extending from an inflated balloon and including tabs andholes which may be used with couplers to couple the implant to the femurof the knee joint.

FIG. 11C depicts a bottom-up view of an embodiment of the unicompartmentknee implant curved to simulate curvature about one condyle of a femur,the implant having appendages extending from an inflated balloon andincluding tabs and holes which may be used with couplers to couple theimplant to the femur of the knee joint.

FIG. 12A depicts a bottom-up view of an embodiment of the unicompartmentknee implant or patch implant, the implant having appendages, extendingfrom a balloon and including holes, which may be used with couplers (notshown) to couple the implant to the femur of the knee joint.

FIG. 12B depicts a bottom-up view of an embodiment of the unicompartmentknee implant or patch implant, the implant having appendages, extendingfrom a balloon and including tabs and a hole which may be used withcouplers (not shown) to couple the implant to the femur of the kneejoint.

FIG. 12C depicts a bottom-up view of an embodiment of the unicompartmentknee implant or patch implant, the implant having appendages, extendingfrom a balloon and including tabs and a hole which may be used withcouplers (not shown) to couple the implant to the femur of the kneejoint.

FIGS. 13A-13D depict multiple views of a staple adapted to couple animplant to a bone of the joint.

FIG. 14 depicts an embodiment of the knee implant having appendagesincluding holes and tabs and including slots to accommodate ligaments ofthe knee joint as well as side views of the same knee implant.

FIGS. 15A, 15B, and 15C show several views of an embodiment of animplant which has no definable chamber, rather the material of theimplant itself provides the cushion to the bones of the joint (atleast).

FIG. 16 depicts a knee implant embodiment that is generally H orV-shaped, having a slot 26 b that is significantly smaller than otherembodiments, and in this embodiment is effectively replaced with a tab10 i at the same location (e.g. 10 i).

FIG. 17 depicts a knee implant embodiment similar to FIG. 16 which showsa posterior view including the location(s) 50 a-50 d where a fillmaterial such as cement may be placed.

FIG. 18 is an anterior-posterior view of an embodiment of the implant 20attached to a knee model.

FIG. 19 depicts an implant 20 which is more squarely cut for interfacewith a femur, for example, which has been cut square such as is done incertain total knee arthroplasty procedures.

FIGS. 20A and 20B depict a knee implant embodiment that is generallyV-shaped or Y-shaped, and in this embodiment the notch 26 b of otherembodiments, or the tab 10 i of other embodiments is effectivelyreplaced with an appendage 4 e at the same location.

FIGS. 21A and 21B depict an oblique posterior view of a knee implantwith medial and lateral appendages.

FIG. 22A depicts a lateral cutaway view of a knee implant.

FIG. 22B depicts a medial cutaway view of a knee implant.

FIG. 23 depicts a posterior view of a knee implant with medial andlateral appendages.

FIG. 24 depicts a side view of a knee implant.

FIG. 25 depicts an oblique view of a right knee implant.

FIG. 26 depicts the bone engaging surface of an implant.

FIG. 27 depicts an isometric view of the joint articulating surface ofan implant.

FIG. 28 depicts a posterior view of implant 20.

FIG. 29 depicts an oblique posterior view of the joint articulatingsurface of an implant.

FIG. 30 is a graph of the radius of curvature profile of a jointarticulating surface along a lateral dimensioned reference line of animplant.

FIG. 31 is a graph of the radius of curvatures profile of a boneengaging surface along a lateral dimensioned reference line of animplant.

DETAILED DESCRIPTION OF THE INVENTION

The present invention is directed to arthroplasty implants andprocedures for a wide variety of joints such as, for example, hips,knees, shoulders, ankles, elbows, wrists, fingers, toes,temporomandibular joints and the like, but for clarity, as well asbrevity, the discussion herein will focus on an implant for a knee jointor hip joint and an implant for replacing the talus bone of a patient'sankle.

Knee interpositional arthroplasty can replace existing total jointmetal/plastic technology. It intends to fill the gap (literally in someembodiments of the implant) in cases where arthroscopic debridementfails to provide cure, since we can only ‘polish arthritis’ and ‘cleanup the joints’ to date. The polymer medically inflatable implants mayphysiologically restore joint function. Padding is provided wherecartilage is damaged, cushioning to both the femoral tibial and patellafemoral joints when narrowed or pathologic. The implant in someembodiments is adapted to deliver cells, autologous (from the patient),allograph (from another member of the same species) or xenograph (fromanother species) that restore articular surfaces. Since cartilage is animmunologically privileged tissue, the antigens are buried in thecartilage matrix and antibodies do not reject the refurbished surfacecoating.

The gap (or gaps) filled by the balloon or balloons of the implant willprovide compliance between opposing joint surfaces (the femoral condyleor condyles and tibial plateau). The femur may have some portion (of notall) of the retropatellar rounded facet “V” shape of hyaline, normallyabout 5 mm thick, or it may not have such hyaline when the implant isinserted. The tibial plateau may have some portion of meniscalfibrocartilages, including all of said fibrocartilages, none of saidfibrocartilages, or some portion thereof. When the knee is extended(straight) the implant buffers the femoro-tibial joint. When the knee isflexed, the implant balloon apposition is more between the trochleargroove portion of the anterior distal femur (groove between the condyleson the ‘front of the knee’) and the patella.

The knee anatomy is unique to other joint anatomies and thus has aunique set of challenges that are addressed by the implant embodimentsdescribed herein. For example, the knee is not a ball and socket jointlike a hip; it is a combination of two joints—the femoral-tibial jointand the patellar-femoral joint. The bones of the knee have facets andirregularities that must be accommodated by a conformable implantdirected to the particular shapes of the bones without impeding thejoints' functions and movements, and/or which minimizes impedence tosuch function and movement. Not only do the joints of the knee worktogether to allow extension and flexion of the knee, but the knee isalso designed to allow rotational movement in a screw-like manner. Thatis, as the tibia is twisted relative to the femur, the joints areuniquely designed to allow this twist, but to limit the twist as well.Furthermore, the knee joints are able to withstand forces that varydepending on the particular movement of the individual, not only inforce strength, but in direction as well. Thus, the implants asdescribed herein are uniquely designed to account for these factors andresult in a knee having preserved natural tissues as well as preservedfunction and movement as compared to typical arthroplasty procedures(such as partial or full knee replacements).

As described herein, embodiments of the implant conform to the patient'sown joint features not only in that it can be pre-molded and/or adaptedto couple to the contours of the patient's bone (condyle, etc), but inthat it has a balloon having an inflation medium that is conformable tothe joint anatomy and allow freedom of joint movement much like naturaljoint while preserving the joint and bone natural tissues as much aspossible. With the ability to fill various chambers of the balloon withvarying materials, and to add rigid and/or semi-rigid pieces to theimplant, the implant can additionally have leveling capabilities andalignment capabilities.

Diagnoses:

Patients may complain of pain and knee joint dysfunction signaled bylocking, clicking, or giving way. Knees may be swollen, malaligned orshow crepitus (palpable crunching on movement.) Instability of ligamentswhether anterior/posterior cruciates, or medial/lateral conlaterals, aretreated by techniques separate for those entities via allowance forhealing (as for collaterals) or via cruciate repair or reconstruction.

Indications for use of implants provided herein may be those patientsrecognizing greater than or equal to 2 Sq cm of 3-4+/4 traumaticarthritis (ala Carticel). In such cases, the cartilage defect is oftenprecisely locally symptomatic, with point tenderness, clicking if aloose cartilage flap exists, and may be visible on MRI and/orarthroscopic inspection and/or through palpation. The implants usedherein may additionally and/or alternatively be appropriate when existedtechniques such as ‘picking’, K wire drills, and/or allograph implantsfail.

Patients with knee problems typically complain of pain and dysfunction.Pathognomonic symptoms for meniscal tearing include locking, clicking,giving way from wear or twisting the knee. Aching diffusely may arisefrom arthritis or synovitis; anterior knee pain is generallypatella-femoral, increased with stair use due to magnified body weightforces. Diagnosis should be accurate as distinguished from pain throughthe knee actually arising in the back caused by L4 nerve rootirritation. Physical Exam findings of pathologic knees include observedswelling, redness, or deformity. Palpation often aids focus on whichcompartments are involved. The patella inhibition test position connotesretropatellar pathology, and often tracking problems that warrant softtissue or boney correct. Improved limb alignment will increase benefits,and can in part accrue from selective inflation of embodiments of theimplants provided herein. X-rays of the knee are best evaluated inweight bearing views, and should be coupled with other data includingMRI or CT. Relative compartment narrowing suggests cartilagedegradation. Once an embodiment of an implant described herein has beensuccessfully implanted and the knee adequately rehabilitated, theappearance of a knee with such implant should resemble a normal jointX-ray. Knee distension is from saline and/or air insufflation. Kneeimplant patients will benefit from tailored rehab programs, cautiousweight bearing, early motion, and potential the use of constant passivemotion machine regimens.

General Features

Implant Aspects

Provided herein is a resilient implant for implantation into knee jointsto act as a cushion allowing for renewed joint motion. The implant mayendure variable knee joint forces and cyclic loads while reducing painand improving function after injury or disease to repair, reconstruct,and regenerate joint integrity. The implant may be deployed in aprepared debrided knee joint space, secured to at least one of the kneejoint bones and expanded in the space, molding to surrounding structureswith sufficient stability to avoid extrusion or dislocation. The implantmay have has opposing walls that move in varied directions, and an innerspace filled with suitable filler to accommodate motions which mimic orapproximate normal knee joint motion. The implant may pad the damagedjoint surfaces, restores cushioning immediately and may be employed torestore cartilage to normal by delivering regenerative cells.

Provided herein is a resilient interpositional arthroplasty implant forapplication into knee joints to pad cartilage defects, cushion joints,and replace or restore the articular surface, preserving jointintegrity, reducing pain and improving function. The implant may endurevariable knee joint compressive and shear forces, and millions of cyclicloads, after injury or disease requires intervention. The implant mayrepair, reconstruct, and regenerate knee joint anatomy in a minimallymorbid fashion, with physiologic solutions that improve upon the rigidexisting joint replacement alternatives of plastic and metal. In caseswhere cells have been used for joint resurfacing requiring massiveperiosteal harvesting for containment, the polymer walls of someembodiments of the implant can capture, distribute and hold living cellsuntil aggregation and hyaline cartilage regrowth occurs. The implant maybe deployed into a prepared debrided knee joint space, molding andconforming to surrounding structures with sufficient stability to avoidextrusion or dislocation. Appendages (or tabs) of the implant may serveto repair or reconstruct tendons or ligaments. The implant may haveopposing walls that move in varied directions, and an inner space,singular or divided, filled with suitable gas, liquid, and/or complexpolymer layers as force-absorbing mobile constituents, such than robustvalid and reliable joint motion is enabled.

Provided herein is a resilient orthopedic implant configured fordeployment between a femur and at least one second bone of a joint. Thesecond bone may be a tibia. The second bone may be a patella. Theimplant further comprises a balloon comprising a first portion that isconfigured to engage the femur, a second portion that is configured toengage the second bone of the joint, a side portion connecting the firstportion and the second portion, in which the side portion facilitatesrelative motion between the first portion and the second portion, and aninterior that is optionally inflatable with a first inflation medium;and a first appendage configured to couple the balloon to the femur. Theterms “balloon” and “bladder” may be used interchangeably throughoutthis disclosure to describe an implant having the features describedherein.

In some embodiments, at least two of the first portion, the secondportion, and the side portion are contiguous. In some embodiments, thefirst portion comprises a first wall, the second portion comprises asecond wall, and the side portion comprises a side wall. As used herein,each of the terms the “first portion”, the “second portion”, and the“side portion” is used to describe a part of the balloon, and may not beseparate parts in some embodiments. Rather, in some embodiments, each isnamed in order to indicate the general geometry and location of eachportion relative to the other of the portions and/or relative to bonesand/or ligaments and/or tendons of the joint. Likewise, as used herein,each of the terms the “first wall”, the “second wall”, and the “sidewall” is used to describe a part of the balloon, and may not be separateparts of the balloon in some embodiments. Rather, in some embodiments,each of the walls is named in order to indicate the general geometry andlocation of each portion relative to the other of the portions and/orrelative to bones and/or ligaments and/or tendons of the joint. In someembodiments, at least two of first wall, the second wall, and the sidewall are contiguous. Nevertheless, each of the walls may, in someembodiments, be separate parts of the implant that are joined to formthe implant. Likewise, each of the portions may, indeed, in someembodiments, be separate parts of the implant that are joined to formthe implant.

In some embodiments, the first portion is a term used interchangeablywith the first wall. In some embodiments, the second portion is a termused interchangeably with the second wall. In some embodiments, the sideportion is a term used interchangeably with the side wall. In someembodiments, a wall (whether a first wall, a second wall, and/or a sidewall) of the implant may comprise a plurality of layers. The wall maycomprise multiple materials to impart physical and/or therapeuticcharacteristics to the wall.

In some embodiments, the implant comprises a second appendage couplingthe balloon to the first bone of the joint. In some embodiments, theimplant comprises a second appendage coupling the balloon to at leastone second bone of the joint. In some embodiments, the implant comprisesa second appendage configured to couple at least one of the firstportion, the second portion, and the side portion to at least one of thefirst bone and at least one second bone of the joint. In someembodiments, the first appendage and the second appendage are configuredto provide ligamentary-like support to the first bone and the at leastone second bone of the joint. In some embodiments, the first appendageand the second appendage are configured to provide ligamentary-likesupport to the joint. In some embodiments, the first appendage and thesecond appendage are configured to provide tendon-like support to thefirst bone and the at least one second bone of the joint. In someembodiments, the first appendage and the second appendage are configuredto provide tendon-like support to the joint.

In some embodiments, the implant comprises an inflation port incommunication with the interior of the balloon for inflation of theinterior of the balloon with the first inflation medium. In someembodiments, the balloon is punctured to inflate the interior of theballoon with the first inflation medium. In some embodiments, theballoon is self-sealing. In some embodiments, the balloon isself-sealing upon inflation of the interior of the balloon with thefirst inflation medium. In some embodiments, the implant comprises aseal capable of closing the interior of the balloon.

In some embodiments, the interior comprises a plurality of inflatablechambers. In some embodiments, the interior comprises a plurality ofindividually inflatable chambers. In some embodiments, a first chamberof the plurality of individually inflatable chambers is adapted to beinflated with the first inflation medium, and a second chamber of theplurality of individually inflatable chambers is adapted to be inflatedwith a second inflation medium.

In some embodiments, the interior comprises a honeycomb structure. Insome embodiments, the interior comprises a mesh structure. In someembodiments, the interior comprises a sponge structure.

In many embodiments the implant (or a portion thereof, such as theballoon or balloons) is a weight bearing spacer that will allow jointmotions to approach normal, whether filling the space left by anentirely collapsed joint bone or the space of ablated cartilageproximate surfaces diffusely as in osteoarthritis or succinctly as inosteonecrotic defects or localized trauma. The walls of the implant maybe used as a membrane for holding living cells in proximity of theosteochondral defect long enough for the cells to attach (e.g. 24 hours)or to deeply adhere (up to 28 days) or return to normal (up to oneyear). Weight bearing will be expected to increase as distal lowerextremity joints are treated.

Movement (whether linear or curvilinear) between the first and secondwalls of the implant (i.e. of the balloon) as a result of movement ofthe femur and the tibia is illustrated in the comparison between FIGS.9B and 10A, or in the comparison between FIGS. 9C and 10B. In someembodiments, the implant may comprise a balloon that is configured toallow a wall of the implant rolling upon another wall (or the same wall)of the implant (e.g. the side wall rolling upon the first wall, thefirst wall rolling upon the second wall, the second wall rolling uponthe first wall, the first wall rolling upon the side wall, the secondwall rolling upon the side wall, the side wall rolling upon the secondwall, the first wall rolling upon the first wall, the second wallrolling upon the second wall, and/or the side wall rolling upon the sidewall). In some embodiments, the implant may comprise a balloon that isconfigured to allow a portion of the implant rolling upon anotherportion (or the same portion) of the implant (for non-limiting example,the side wall rolling upon an appendage, the first wall rolling upon anappendage, and/or the second wall rolling upon an appendage). In someembodiments, the implant may comprise a balloon that is configured toallow movement of a portion of the implant rolling upon cartilage. Whilenot shown in the drawings, there may be slippage between the a portionof the implant (whether an appendage, a wall, or some other portion ofthe implant) and a joint component (whether a bone, ligament, tendon orother tissue). This slippage may be in addition to wall movements withinthe implant per se to provide desired joint movements. While not shownin the drawings, there may be slippage between the second bone (forexample, the tibia) and the second wall in addition to wall movementswithin the implant per se to provide desired joint movements. Theappendage (or appendages) is (are) designed to secure the implant to theknee joint structure so as to avoid dislocation of the implant. Movementof the joint with the implant in place will be a shared function of boththe moving opposing walls of the implant but also a function of themovement of the wall which may be less attached to the joint members.There may be slight movement between the appendage, first wall and thefemur. The walls of the balloon may compress and/or stretch toaccommodate bone interface movement. Material choices, materialdimensions, and implant dimensions, placement and/or coupling may bechosen to allow for the desired amount of compression, stretchingrelative movement of various joint and/or implant components. Fornon-limiting example, the walls of the implant may be thicker is someareas to accommodate particular loads and the side wall may be thinnerand more elastic to accommodate rolling and stretching thereof.

Motion is believed to be primarily between the spaced walls (orportions) of the implant peripherally secured to joint structures,although some motion may occur between the implant and the jointsurfaces. As shown multiple Figures (including, FIGS. 1-7), the implantmay be provided with a slot extending from the periphery of the implanttoward the balloon of the implant to accommodate at least one ligamentof the joint. Knee implants may have two slots leading to separatepassages for receiving the anterior and posterior cruciate ligaments.Implant walls should have sufficient inherent flexibility to mold to theexisting deformities imposed by either natural ligament, bone, tendonand remaining cartilage deformities of the internal joint space filledas a cushion. The wall exteriors may be flat or formed with random orspecific patterns for purposes of glide or trends for traction againstadjacent surfaces, or as sulci or venues for cell delivery materials.

The exterior of the implant may have a mesh material with a plurality ofchords (or appendages) for securing the implant to adjacent bones or toremnant ligaments which are attached to adjacent bones.

The dimensions of the various implant walls will vary depending upon thematerial properties thereof as well as the needs for a particular joint.Additionally, the first and second walls may require a thicknessdifferent from the side wall. Generally, the implant may have a wallthicknesses of about 0.125 mm to about 3 mm, preferably about 0.5 mm toabout 1.5 mm. The spacing between the first and second wall within theinterior can vary from about 0.5 mm to about 5 mm.

In some embodiments, the implant has a first wall, a second wall, and aside wall which define the implant interior (or interior) which containsfilling material. In some embodiments, the filling material is aninflation medium. The first wall is secured to the end of the femur byat least one appendage that extends from the first wall and the secondwall engages the end surface of the second bone (which in the case of afemoral-tibial joint implant, would be the tibia) and may also besecured thereto. The side wall extending between the first and secondwalls defines at least in part the implant interior which is filled withfilling material (or an inflation medium). The inner surfaces of walland appendage may conform to the particular surface femur, for exampleby being wider in particular locations and/or longer in particularareas. For example a dual compartment implant (described herein) mayhave a wider section to cover the medial condyle than the lateralcondyle (as shown in FIGS. 1, 2, 3, 6A, 6B, and 7). In another example,the length of the implant the along the external edge may be longer thanthe length of the implant along the trochlear groove edge (as shown inFIGS. 11A, 11B and 11C). In yet another example, the width may varyalong a single condyle, such as is shown in FIGS. 12A-120, wherein thewider edge of the implant is adapted to fit over at least a portion ofthe anterior condyle, and the narrower portion is adapted to fit over atleast a portion of the posterior condyle. In some embodiments, the innersurfaces of the first wall and appendages preferably conform to theparticular surface of the patient's femur, and do so by not onlydimensions of the implant (lengths, widths, balloon location and shape),but also and/or alternatively due to appendage and/or tab and/or holeand/or coupler location and/or surface contours of the first wall. Theouter surface of the second wall may be configured to conform to the endsurface of the second bone (which may be a tibia or a patella, forexample). In some embodiments, the outer surface of the second wall isconfigured to conform to a surface of the second bone (which may be atibia or a patella, for example). The figures provided herein are highlyschematic and do not depict details of the joint surface features, sincehuman pathology and variation reflects both the patient's immediate andevolving pathophysiology. Neither do the figures depict other jointfeatures such as cartilage, tendons, ligaments and other soft tissuesand fluids of the joint for ease of viewing that which is depicted.

In some embodiments, the implant is configured to resemble the shape ofthe natural hyaline of a normal knee. For example, the normal hyaline istypically “H” shaped, thus certain embodiments of the implant aregenerally “H” shaped.

Implant Materials and Material Features

In some embodiments, the implant comprises polymer. Polymers maycomprise at least one of: a polyurethane (such as, for example,ChronoFlex AR), a polycarbonate urethane, a thermoplastic polycarbonateurethane (such as Bionate 55, Bionate®80, Bionate®80A), ethylene-vinylacetate copolymer, multiblock copolymers of poly(ethylene oxide) (PEO)and poly(butylene terephthalate) (PBT), PEG, PEO, and a polyetheylene.In some embodiments the implant comprises a 125 micron thicknessthermoplastic polycarbonate urethane.

The implant may comprise to a plurality of layers of polymer (such asChronoFlex AR) in a solvent and evaporating the solvent after applyingeach layer. In some embodiments, the implant comprises a polyurethanethat is sprayed and dried (wherein the spraying and drying is repeatedat least once) to a desired thickness.

In some embodiments, the implant comprises polymer. Polymers maycomprise at least one of: a polyurethane (such as, for example,ChronoFlex AR, ChronoFlex AL®, ChronoFlec C®), a polycarbonate urethane,a thermoplastic polycarbonate urethane (such as BIONATE®, e.g., BIONATE®I, BIONATE® II, BIONATE® 55D, BIONATE® 65D, BIONATE® 75D, BIONATE® 80A,BIONATE® 90A, BIONATE® 55 or BIONATE® 80), ethylene-vinyl acetatecopolymer, multiblock copolymers of poly(ethylene oxide) (PEO) andpoly(butylene terephthalate) (PBT), PEG, PEO, and a polyetheylene.

The implant may comprise to a plurality of layers of polymer (such asChronoFlex AR, ChronoFlexAR®, ChronoFlex AL®), ChronoFlec C®) in asolvent and evaporating the solvent after applying each layer. In someembodiments, the implant comprises a polyurethane that is sprayed anddried (wherein the spraying and drying is repeated at least once) to adesired thickness.

The implant may be formed of suitable bioabsorbable materials so thatthe implant may be absorbed within a particular predetermined timeframe. Suitable bioabsorbable materials include polylactic acid,polyglycolic acid, polycaprolactone, copolymers, blends and variantsthereof. Suitable bioabsorbable materials may also/alternatively includepoly(hydroxyalkanoate)s of the PHB-PHV class, additional poly(ester)s,and natural polymers, particularly, modified poly(saccharide)s, e.g.,starch, cellulose, and chitosan. The walls of the implant may be (inwhole and/or in part) bioabsorbable. The balloon may be (in whole and/orin part) bioabsorbable. As used herein the terms bioabsorbable,bioerodable, and/or bioabsorbable may be used interchangeably. The wallsof the implant may release a pharmaceutical agent or an biological agent(such as stem cells, differentiated cells, pluripotent cells,post-mitotic cells, living chondrocytes, gene therapies, and the like).The release of such agents (whether biological or pharmaceutical, or acombination thereof) may occur over time, as the wall of the implant (oras the balloon) bioabsorbs in some embodiments, or as the joint is used(i.e. through pressure, for non-limiting example). In some embodiments,at least one of the implant walls is permeable to a pharmaceutical agentand/or a biological agent, such as in an embodiment wherein theinflation medium comprises the pharmaceutical agent and/or biologicalagent. In some embodiments, at least one of the implant walls has poresthrough which the pharmaceutical agent and/or the biological agent mayfit, such as in an embodiment wherein the inflation medium comprises thepharmaceutical agent and/or biological agent. In some embodiments thecontents may contain targeting drugs such as gleevac that turn off tumormolecules as those in GIST. Cell-specific drugs targeting tumors bydesign may require nano-sized micelles with hydrophilic shells toprotect core agents. In some embodiment hydrogels are used and tailoredto swell thus releasing trapped molecules or cells through weblikesurfaces, controlled by internal or external triggers such as ph,magnetic fields, or temperature. Dendritic macromolecules may be used inimplants to deliver agents en masse deploying a controllable size andstructure. In some embodiments, individual agent molecules or hubs maybe incorporated via covalent bonds.

In some embodiments, the implant is created by dip molding a mandrelhaving a shape of a bone of the knee joint (the medial condyle, thelateral condyle, the tibia, for non-limiting example) into a polymersolution (for non-limiting example, a urethane polymer such asChronoflex). Following each dip, the implant is dried for a specifiedtime, which may be, for example, about 3 seconds, about 4 seconds, about5 seconds, about 6 seconds, about 7 seconds, about 8 seconds, about 9seconds, about 10 seconds, about 15 seconds, about 20 seconds, about 25seconds, about 30 seconds, about 45 seconds, about 1 minute, about 2minutes, about 5 minutes, about 10 minutes, about 15 minutes, and overabout 15 minutes. The term “about” used herein in reference to dryingtime of the implant can mean variations of at least one of 5%, 10%, 25%,and 50%, In some embodiments, no drying step is used. The dipping may berepeated multiple times. In some embodiments a single dip is sufficient.In some embodiments, the dipping is repeated 2 times. In someembodiments, the dipping is repeated 3 times. In some embodiments, thedipping is repeated 4 times. In some embodiments, the dipping isrepeated 5 times. In some embodiments, the dipping is repeated 6 times.In some embodiments, the dipping is repeated 7 times. In someembodiments, the dipping is repeated 8 times. In some embodiments, thedipping is repeated 9 times. In some embodiments, the dipping isrepeated 10 times. In some embodiments, the dipping is repeated 11times. In some embodiments, the dipping is repeated 12 times. In someembodiments, the dipping is repeated 13 times. In some embodiments, thedipping is repeated 14 times. In some embodiments, the dipping isrepeated 15 times. In some embodiments, the dipping is repeated 16times. In some embodiments, the dipping is repeated 17 times. In someembodiments, the dipping is repeated 18 times. In some embodiments, thedipping is repeated 19 times. In some embodiments, the dipping isrepeated 20 times. In some embodiments, the dipping is repeated 21times. In some embodiments, the dipping is repeated 22 times. In someembodiments, the dipping is repeated 23 times. In some embodiments, thedipping is repeated 24 times. In some embodiments, the dipping isrepeated 25 times. In some embodiments, the dipping is repeated over 25times. In some embodiments, the dipping is repeated a sufficient numberof times to create an implant that is a prescribed thickness. Thethickness may vary depending on the polymer and depending on theembodiment of the implant. The thickness may be at least one of: about25 microns thick, about 50 microns thick, about 100 microns thick, about125 microns thick, about 150 microns thick, about 200 microns thick,about 250 microns thick, about 300 microns thick, about 350 micronsthick, about 400 microns thick, about 25-50 microns thick, about 50-100microns thick, about 50-200 microns thick, about 100-150 microns thick,about 150-300 microns thick, about 100-300 microns thick, about 100-500microns thick, about 200-500 microns thick, and about 200-1000 micronsthick. The term “about” used herein in reference to thickness of theimplant can mean variations of at least one of 5%, 10%, 25%, and 50%,The thickness may vary at different locations of the implant. In someembodiments, the implant is fabricated in two pieces, one or more ofwhich is molded to form an interior when the two pieces are puttogether. In some embodiments, the implant is filled by puncturing theimplant wall and sealing the puncture hole with a plug, patch or othersealant. The plug, patch, or other sealant may comprise Chronoflexmaterial, for non-limiting example. The plug, patch, or other sealantmay comprise the same material from which the implant is constructed,for non-limiting example.

The walls of the implant embodying features of the invention may becomposite structures. For example, the innermost layer may be imperviousto preclude escape of inflation or other filling media, a central layermay be porous or otherwise contain treatment or cell regenerationagents, and the outer layer may be a thin, but strong layer of athermoplastic, such as a thermoplastic polyurethane for non-limitingexample, which has microporosity sufficient to allow passage or egressof treatment or cell regeneration agents from the central layer (orsecond layer). The degree of microporosity to enable egress of treatmentor cell regeneration agents from the central layer is found in polymerlayers such as Chronoflex or Bionate 55.

The external wall (and/or the bone engaging surface) of the implant maybe coated and/or impregnated with a latticework of polymer that issurface sprayed or layered on the outside (or bone engaging surface) ofthe implant to promote cartilage tissue regeneration. This most externalsurface coating may contain living chondrocytes (for example, as isprovided in the Carticel procedure by the Genzyme company), and/or maycontain stem cells with directed gene mutations to enhance adherence ofthe coating to the implant. The bone engaging surface may comprise peaksand troughs. The living cells may be imposed in between (and/or providedin the) troughs of the implant surface while the surface areas ofprominence (the peaks of the surface) may be used for at least one of:space validation, traction, and cell protection. The bone engagingsurface may have a roughness to it or may have a different texture thanthe articulating surface. The articulating surface may be smooth.

The implant may be formed of suitable bioabsorbable materials so thatthe implant may be absorbed within a particular predetermined timeframe. Suitable bioabsorbable materials include polylactic acid,polyglycolic acid, polycaprolactone, copolymers, blends and variantsthereof. Suitable bioabsorbable materials may also/alternatively includepoly(hydroxyalkanoate)s of the PHB-PHV class, additional poly(ester)s,and natural polymers, particularly, modified poly(saccharide)s, e.g.,starch, cellulose, and chitosan. The walls of the implant may be (inwhole and/or in part) bioabsorbable. The balloon may be (in whole and/orin part) bioabsorbable. As used herein the terms bioabsorbable,bioerodable, and/or bioabsorbable may be used interchangeably. The wallsof the implant may release a pharmaceutical agent or an biological agent(such as stem cells, living chondrocytes, gene therapies, and the like).The release of such agents (whether biological or pharmaceutical, or acombination thereof) may occur over time, as the wall of the implant (oras the balloon) bioabsorbs in some embodiments, or as the joint is used(i.e. through pressure, for non-limiting example). In some embodiments,at least one of the implant walls is permeable to a pharmaceutical agentand/or a biological agent, such as in an embodiment wherein theinflation medium comprises the pharmaceutical agent and/or biologicalagent. In some embodiments, at least one of the implant walls has poresthrough which the pharmaceutical agent and/or the biological agent mayfit, such as in an embodiment wherein the inflation medium comprises thepharmaceutical agent and/or biological agent.

The implant may be provided with latticework or other reinforcingstrands, preferably on the exterior or within the wall thereof tocontrol the maximum expansion of the implant when deployed at theorthopedic site.

In some embodiments, the implant comprises amniotic membrane (and/or acomponent thereof). In some embodiments, the implant comprises amnioticsac (and/or a component thereof). In some embodiments, the implantcomprises amniotic tissue (and/or a component thereof). Amnioticmembrane (and/or sac and/or tissue) is unique in that its mechanicalproperties include that it slippery on one side (lubricious, low modulusof elasticity) and sticky (adherent) on the other. In some embodiments,at least one of the first wall, the second wall and the side wallcomprise amniotic membrane or a component thereof. In some embodiments,at least one of the first wall, the second wall and the side wallcomprise amniotic sac or a component thereof. In some embodiments, atleast one of the first wall, the second wall and the side wall compriseamniotic tissue or a component thereof. The amniotic membrane and/oramniotic sac and/or amniotic tissue may be used in conjunction withother biologic agents, pharmaceutical agents, and/or therapeutic agents.Amniotic tissue is used extensively in pleuripotential cells. Itqualifies as HTBP (Human Tissue Based Product) because of the short termtime span on the product and origin.

In some embodiments, the balloon is a composite structure. In someembodiments, the balloon comprises layers of porous and/or non-porousmaterials, or otherwise contain treatment or cell regeneration agents.In some embodiments, a first layer of the balloon is a thin, but stronglayer of a thermoplastic, such as a thermoplastic polyurethane, fornon-limiting example, which has microporosity sufficient to allowpassage or egress of treatment or cell regeneration agents from a secondlayer. The second layer may be a central layer (which lies between thefirst layer and a third layer or a fourth layer or more layers). Thefirst layer may comprise a bone engaging surface in some embodiments.The degree of microporosity to enable egress of treatment or cellregeneration agents from the second layer is found in polymer layerssuch as Chronoflex or Bionate 55. The bone engaging surface of theimplant may be coated and/or impregnated with a latticework of polymerthat is surface sprayed or layered on the bone engaging surface of theimplant to promote cartilage tissue regeneration. This bone engagingsurface coating may contain living chondrocytes (for example, as isprovided in the Carticel procedure by the Genzyme company), and/or maycontain stem cells with directed gene mutations to enhance adherence ofthe coating to the implant. The bone engaging surface may comprise peaksand troughs. The living cells may be provided in troughs while thesurface peaks may be used for at least one of: space validation,traction, and cell protection.

In some embodiments, the implant is pre-molded to fit about at least onecondyle of the femur. In some embodiments, the implant comprises amemory plastic. In some embodiments, the implant comprises a wire frame.In some embodiments, the wire of the wire frame comprises a memorymetal. In some embodiments, the memory metal comprises nitinol. In someembodiments, the wire frame is disposed in the periphery of the implantor a portion thereof. In some embodiments, the wire frame is configuredto aid in placement against the posterior of the condyle.

In some embodiments, at least a portion of the implant comprises aslippery surface. In some embodiments the slippery surface is configuredto allow for relative movement between the implant (or a portionthereof) that is coupled to the femur and the tibia. In some embodimentsthe slippery surface is configured to allow for relative movementbetween the implant (or a portion thereof) that is coupled to the femurand the patella.

Inflation Medium and Inflation or Filling of the Implant Interior

In some embodiments, the implant comprises an inflation medium that iscompressible. In some embodiments, the implant comprises an inflationmedium that comprises a viscolubricant. In some embodiments, the implantcomprises an inflation medium that comprises a pharmacologic substance.In some embodiments, the implant comprises an inflation medium thatcomprises an NSAID. In some embodiments, the implant comprises aninflation medium that comprises chondrocytes. In some embodiments theimplant is configured to anneal the outer most layer of the implant (ora portion thereof) to the peripheral of succinct cartilage defects so asto cover them, allowing for healing. In some embodiments the implant isconfigured to anneal the outer most layer of the implant (or a portionthereof) to the peripheral of succinct cartilage defects so as to coverthem, allowing for healing once new chondrocytes have been installed.

The implant interior (balloon interior) may be inflated with gas. Theimplant interior (balloon interior) may be inflated with liquid. Theimplant interior (balloon interior) may be inflated with saline. Theimplant interior (balloon interior) may be inflated with suspended stemcells. The implant interior (balloon interior) may be inflated with gel.The implant interior (balloon interior) may be inflated with aviscolubricant. The inflation medium in some embodiments stays withinthe balloon, or a portion thereof (as where there are multiple chambersto the balloon). In some embodiments, balloon contents disburse throughmicroporosities and/or dissolving membranes into the joint. In someembodiments, balloon contents disburse by expulsive or evacuationprecipitated through an implant wall after pressure from limb use. Insome embodiments, balloon contents disburse by expulsive or evacuationprecipitated through an implant wall from planned osmosis. In someembodiments, balloon contents disburse by expulsive or evacuationprecipitated through an implant wall from vacuole rupture (whethermechanical rupture, ultrasound, or chemical rupture, for non-limitingexample). In some embodiments, balloon contents disburse by expulsive orevacuation precipitated through an implant wall thereby distributingcontents of the implant interior to joints as lubricious, analgesic,anti-inflammatory and/or otherwise healing substances. In someembodiments, the implant may comprise solid beads or beads containinggel or liquid for sequential disbursement by compressive force throughrupture with varied bead wall thicknesses, or the beads may betime-released (opened) chemically, pharmacologically, or by an outsideultrasound or magnetic force external knee application at appropriateclinical intervals. In some embodiments, the implant may comprisevacuoles containing gel or liquid for sequential disbursement bycompressive force through rupture with varied vacuole wall thicknesses,or the vacuoles may be time-released (opened) chemically,pharmacologically, or by an outside ultrasound or magnetic forceexternal knee application at appropriate clinical intervals.

The implant interior (or balloon interior) between the first wall andthe second wall is filled with filler material (or an inflation medium)which aids in maintaining the desired implant dynamics within the jointstructure. The nature of the filler material such as a fluid and thecharacteristics of the walls may be selected to maintain a desiredspacing between the walls in order to accommodate the pressure appliedby the bones of the joint structure to the implant and to allow suitablemotion between the first and second walls of the implant whichfacilitate bone motion which mimics or approximates normal movement forthe joint members involved.

Alternatively (and/or additionally), the inner chamber (interior or aportion thereof) may be filled with resilient material to provide thedesired spacing, pressure accommodation, while allowing desiredphysiologic motion between implant layers. The implant may be configuredto be shaped like the joint space and bone surfaces being replaced or tofill the void produced by injury or disease so that the natural jointspacing and cushioning of the joint interface is restored toward normalphysiologic appearance and function. Fluids such as saline, mineral oiland the like may be employed to inflate the implant.

The interior of implant is adjustably filled by the physician from anappropriate source thereof after the implant is deployed to ensure thatthe pathologic joint space becomes a resilient cushion again which aidsrestoration of worn or damaged cartilage interfaces in the joint bycovering cartilage defects with the implant material, cushioning thejoint and defects therein and delivering cell regeneration agents. Inone embodiment, the implant comprises a bio-compatible inflatable member(balloon) that is filled with a biocompatible fill material (inflationmedium) such as a gas, liquid, gel or slurry, or fluid that becomes aresilient solid to provide relative movement between the first andsecond walls. The filling or inflation media may be inserted through aninjection valve site leading to the cannula which delivers the materialinto the interior of the implant. In an alternative embodiment, theimplant may be filled with or have an interior formed of biologicallycompatible resilient material, e.g. a closed cell sponge filled withsuitable fluid that is inserted into the interior of the implant priorto the implant's deployment or injected into the interior after theimplant is deployed at the joint site. The interior of the implant maybe provided with lubricious material to facilitate movement between theinner wall surfaces and to minimize contact wear therebetween. Thepolymeric walls of the implant may be impregnated with or otherwisecarry tissue regeneration agents such as stem cells, livingchondrocytes, and/or genes to repair joint surfaces.

In some embodiments, the first inflation medium imparts rigidity in theimplant. In some embodiments, the first inflation medium imparts cushionin the implant. In some embodiments, the inflation medium chosen for thefirst inflation medium, and/or the particular choice of chamber (inembodiments having multiple chambers) filled with such first inflationmedium aligns the joint. In some embodiments, the inflation mediumchosen for the first inflation medium, and/or the particular choice ofchamber (in embodiments having multiple chambers) filled with such firstinflation medium aligns the bones of the joint. In some embodiments, theinflation medium chosen for the first inflation medium, and/or theparticular choice of chamber (in embodiments having multiple chambers)filled with such first inflation medium changes the bone alignment. Insome embodiments, the inflation medium chosen for the first inflationmedium, and/or the particular choice of chamber (in embodiments havingmultiple chambers) filled with such first inflation medium improvesjoint alignment. In some embodiments, the inflation medium chosen forthe first inflation medium, and/or the particular choice of chamber (inembodiments having multiple chambers) filled with such first inflationmedium restores, at least in part, joint alignment. In some embodiments,individual chambers of the interior may be selectively inflated with afirst inflation medium and/or a second inflation medium. In someembodiments, individual chambers of the interior are selectivelyinflated with a first inflation medium and/or a second inflation mediumin order to reconstruct the joint and/or bones of the joint.

In some embodiments the inflation medium comprises living chondrocytes.

The implant interior (balloon interior) may be inflated withmethymethacrylate as a liquid that becomes a solid or semi-solid (rigidor semi-rigid). In some embodiments, the inflation medium is a methylmethacrylate or other biocompatible hardening substance which can flowwhen initially put into the chamber, and hardens to become a rigid pieceor semi-rigid piece or solid piece. The methyl methacrylate or otherbiocompatible hardening substance may conform to the shape of thechamber, or may conform to the shape of a space between bones and/orother joint structures. The methyl methacrylate or other biocompatiblehardening substance may conform to a form chosen by the surgeon usingtools and/or pressure to influence the final shape of the rigid pieceformed by the methyl methacrylate or other biocompatible hardeningsubstance upon hardening.

The side wall extends between the first and second walls to form aninterior which receives filling material through tube (also called aconduit herein, or may be called an inflation port). In someembodiments, the inflation port is not a tube, but is a valve which mayor may not extend from a wall of the implant. The valve may be part of awall of the implant, or part of the balloon or a portion thereof. Theimplant would also be appropriate for one condyle of the knee, but othershapes may be desired for other joint configurations whether relativelyflat or more inflated toward a ballooning construct. In someembodiments, the inner diameter of the inflation port (or tube) is 5millimeters maximum. In some embodiments, the inner diameter of theinflation port is about 1 millimeter. In some embodiments, the innerdiameter of the inflation port is about 2 millimeters. In someembodiments, a needle (of typical needle sizes) may be used to inflatethe implant.

A separate portal or tube (not shown) or the existing conduit (tube orvalve), may be used to extract noxious inflammatory enzymes that can beaspirated at appropriate clinical intervals. Inflammatory enzymes in theCOX1, COX2 and or 5LOX pathways can be extracted. Viscolubricants can beinjected into the interior of the resilient arthroplasty implant throughexisting conduit or through a long needle to aide in distension,expansion, lubrication (with predetermined microporosity).

In some embodiments, an inflation medium that generates heat (by meansof a catalyst reaction or other means) may be used to deliver heat to ajoint structure. The heat may aide hyaline cartilage annealing. Thermaleffects of the implant materials are calculated accordingly to benefitand protect the joint surface analogous to a dry suit or wet suit for ascuba diver exposed to temperature extremes. Embodiments of the implantgenerally seek to avoid head from friction via lubricious coatingswhether allograph as amniotic membrane or polymer, for non-limitingexample.

The implant design allows for ease of implantation. In one embodiment,the implant can be inserted into the knee joint via a cannula. Becauseof the design of the implant, the implant may be inserted into the jointcapsule. In one embodiment, the implant, is deployed into the jointcapsule.

The implant in some embodiments is inserted arthroscopically through acannula about 10 mm in diameter with the implant in the deflatedconstruct, and once inside the prepared joint space and secured thereinby the appendages or tabs, the implant will be distended or inflatedwith gas, gel, fluid or fluid that becomes a resilient solid to fill theoriginal natural space of a bone of the joint (whether the tibia, femuror patella). Tensioning will be by the surgeon's sense of properpressure application aided by a gauged syringe for insertion ofviscolubricants such as Synvisc, Hyalgan, Supartz and/or analgesics suchas lidocaine gel. The insertion of liquids to the joint per se may bedirectly, through a cannula to the joint space previously in place fordebridement, and or via a cannula or tube that is not part of theoriginal implant assembly. Once the joint is cleaned, the implant isinserted and appropriately fixed to avoid extrusion or dislocationthereof. This may be via attachment of the implant tabs and/or by acombination of tab use plus intended friction created by implant surfacecoverings (analogous to Velcro) or a draw string at the smaller base ofthe implant.

Attachment Elements and Couplers

In some embodiments the attachment elements of the implant comprisesholes through which screws or other couplers may be placed to attach theimplant to an attachment site (or connection site) in the bone of theknee. In some embodiments, the holes are created arthroscopically. Insome embodiments the holes are pre-fabricated in the implant. In someembodiments, the holes may be made prior to implantation based on thepatient's particular anatomy. In some embodiments, the holes arereinforced by a reinforcing material of the implant. The reinforcingmaterial may be a polymer of sufficient durometer and/or tear resistanceto reinforce the screw hole. The reinforcing material may be comprisemetal. In some embodiments, there is no pre-formed hole, but ratherscrews (or another coupler) secure the attachment tabs (which may be anon-balloon portion of the implant) to the joint component (bone, etc)by creating their own hole when implanted. In some embodiments, theimplant may comprise tabs that are adapted to receive staples or othercouplers described elsewhere herein.

The implants described herein may comprise attachment elements (or tabs)which may then by attached or coupled to tissue of a component of thejoint (whether to a bone or a ligament or a tendon or other jointcomponent) by a coupling device. Coupling devices (or couplers) maycomprise at least one of screws, washers, sutures, suture anchors (metaland/or biodegradable), rivots, staples (with and/or without teeth),stabilizers, glues, hooks of cylindrical wire or flattened sheet metalinto bone holes or slots respectively. The coupling devices may beresorbable or not. Also, the coupling devices may comprise at least oneof strings (i.e. drawstrings), reigns, lassos, sutures, and lanyards.The strings, reigns. lassos, sutures, and/or lanyards may join withthemselves and/or other coupling devices. The strings, reigns. lassos,sutures and/or lanyards may be directed not only into bone with orwithout anchors, but also through ligaments, tendons or loose segmentsof cartilage that the surgeon intends to preserve.

The implant may be affixed to the femur. The methods to affix, secure,anchor, screw or stabilize the implant are described herein. The implantcan be secured in a manner designated by one of ordinary skill in theart. In one embodiment, the implant may have pre-fabricated holes toallow for screws or other types of anchoring devices. The implant mayhave from 0-20 holes. Preferably, there are 3-10 holes. A preferredembodiment is disclosed which comprises 5 holes. In one embodiment, onehole is specifically located on the implant in a location adjacent thecondyle notch of the knee. The holes may be 0.01 mm to 30 mm indiameter. Preferably, the diameter of the holes is from 0.5 to 7 mm.More preferably the diameter of the holes is from 2 to 5 mm. In someinstances, the holes have a 4.5 mm diameter. In other instances, eachhole has a different diameter. In still another instance, some holes mayhave a first diameter while other holes a second or third diameter. In apreferred embodiment, the holes are circular, however the holes may besquare, rectangular, crescent shaped, or any appropriate shape foraiding in the coupling or attaching of the implant to an area in thejoint such as to bone. The part of the implant defining the holes can bemade of the same or a different material so as to fortify or strengthenthe implant near or around the anchoring or coupling means.

The implant can be secured with a coupling device as described herein.In some embodiments, from 0 to 30 coupling devices are used. Morepreferably, from 5 to 10 coupling devices are used.

In some embodiments the implant is fashioned for a left knee. In otherembodiments the implant is fashioned for a right knee. The rim mayengage a bone or cartilage. The rim may comprise a scaffold. The rim mayengage the joint capsule. The rim may be filleted or demonstrate avariable fillet. In a separate embodiment, the rim may be raised.

In some embodiments, the implant is of a standard size. In otherembodiments, the implant is fitted for a right knee. In otherembodiments, the implant is fitted for a left knee. In some embodiments,the appendage that engages the medial femoral condyle is larger than theappendage which engages the lateral femoral condyle.

The posterior of the knee can be difficult to access without disturbingjoint components (or in order to minimize such disturbance) such astendons, ligaments, etc. Thus, in some embodiments, the implantcomprises strings, reigns. lassos, and/or lanyards that may pass fromthe posterior of the implant via the intercondylar notch anteriorly tojoin with themselves and/or other coupling devices. These couplers maybe pre-coupled to the implant, and the implant and its couplers may beconfigured to be pulled (or cinched) from the anterior of the implantonce the implant is in its general location relative to the condyle inorder to finally position the implant about the condyle—in particular inorder to cinch the implant about the posterior of the condyle. Likewise,in some embodiments where the implant is pre-molded, the coupler asdescribed are adapted to move the implant to its final position withconformity to the condyle's posterior with minimal disturbance to thejoint structures at the joint's posterior (minimal cutting, minimalmoving, and or minimal detachment, for non-limiting example).

In some embodiments, the implant comprises a skirt (or sleeve) thatconforms to the contours of the bone (whether a condyle of the femur, apatella, or a tibia) as a coupler.

In some embodiments, a screw through tab having reinforced center holesmay be part of the implant. For example, the implant may comprisepolymer covered metal washer holes. The screw may go through the holes.Another embodiment may comprise a staple having spikes as shown in FIGS.13A-13D. FIGS. 13A-13D depict multiple views of a staple adapted tocouple an implant to a bone of the joint. FIG. 13A depicts an embodimentof an implant 20 having a tab 10 a that is coupled to bone using astaple 12. FIGS. 13B & 13C depict a staple 12 as described herein havingteeth 18. FIG. 13C depicts an embodiment of a tab 10 a that is coupledto bone using a staple 12 having teeth 18. Combinations of spikes andscrews may be used in some embodiments, or combinations of othercouplers. The implant may be configured to allow a surgeon the option ofseveral types and sizes of couplers, as each patient differs with regardto size and depth of lesion, bone stock, regrowth capability, andcompliance with advised recovery, and each surgeon has his own strengthsand comforts when working with such implants.

The edge of the implant may have a depending skirt to secure or anchorthe implant to the end of bone (femur), but may have one or moredepending tabs (or appendages) that may be employed for similarfunctions as will be discussed in other embodiments. The skirt (and/ortabs, and/or appendages) may tightly fit about the end of the femur, orthe skirt can be secured by adhesive (e.g. methyl methacrylate, boneingrowth) to the supporting bone structure or be mechanically connectedby staples, screws and the like. Moreover, the lower portion of theskirt may be secured by a purse string suture or a suitable strand(elastic or tied) that is tightly bound about the outside of the skirt.

FIGS. 12A, 12B, and/or 12C alternatively may be used to describe a patchimplant or a unicompartment knee implant described herein, havingappendages 4 a, 4 c, extending from a balloon 6 and including holes 8 a,8 b, 8 c, and/or tabs 10 a, 10 b. 10 c, 10 d, 10 e, 10 f, which may beused with couplers (not shown) to couple the implant to a bone of theknee joint (which may be the femur, the tibia, or the patella). Featuresshown in FIGS. 12A, 12B, and or 12C are common to both theunicompartment knee implant (also discussed elsewhere herein) and thepatch implant (also discussed elsewhere herein), although dimensions maydiffer as described elsewhere herein.

FIGS. 13A-13D depict multiple views of a staple 12 adapted to coupleimplant 14 (such as those described herein) to a bone 16 of the joint.FIG. 13A depicts a staple 12 coupling a tab 10 a of an appendage 4 a tothe bone 16 of the joint (wherein the portion of the staple 12 embeddedin the bone 16 is shown as a dashed line). FIG. 13B depicts a view of astaple 12 having teeth 18 to grasp the tab 10 a of the implant 14.Similarly, FIG. 13C depicts a view of a staple 12 having teeth 18 tograsp the tab 10 a of the implant 14. FIG. 13D depicts a staple 12attaching the tab 10 a of an implant to a bone 16, the dotted lines showthe portion of the tab 10 a that is compressed by the staple 12 andteeth 18 thereof.

For example, FIG. 14 depicts an embodiment of the knee implant 20 havingappendages 4 a, 4 b, 4 c, 4 d, including holes 8 a, 8 b, 8 c, 8 d andtabs 10 a, 10 b and including slots 26 a, 26 b to accommodate ligamentsof the knee joint as well as side views of the same knee implant.Couplers as described elsewhere herein may be used to couple the implant20 to the distal femur. In some embodiments, there may only tabs, onlyholes, or only appendages, or combinations thereof. In some embodiments,there may be other ways to couple the implant to the distal femur, asdescribed elsewhere herein (sutures, drawstrings, skirts, glue, etc). Insome embodiments, the couplers create the holes 8 a, 8 b, 8 c, 8 d, orother holes (not shown) when the implant is placed against the distalfemur. In some embodiments, the holes are pre-formed in the appendageprior to implantation. In some embodiments, the holes are reinforced asdescribed elsewhere herein. As shown here, the appendages in someembodiments are different in shape and/or size to accommodate thedifferences in condyle size and/or shape. For example the medial condyletends to be larger than the lateral condyle, and thus appendage 4 d thatis intended to wrap over the medial condyle may be longer and/or widerthan the appendage 4 c intended to wrap over the lateral condyle. Shownin the embodiment depicted in FIG. 14 are the different hole placementsfrom the side view, showing the differences in positioning of the holesto accommodate the differences in anatomic structure and size of thecondyles. Likewise, the slots may be different in shape and/or sizeand/or position to accommodate the ligaments and/or tendons of the jointor other structures and functions of the joints of the knee, and toallow for placement of the implant with minimal disturbance (cutting,manipulation, for example) of the joint components such as tendons,ligaments, and other soft or hard tissues. For example, slot 26 a isshaped and positioned to accommodate the cruciate ligaments of the knee,at least. Additionally, as shown in the side views of the embodimentshown in FIG. 14, the implant has a first wall 28 adapted to be adjacentthe femur that is of approximately the same thickness than the secondwall 30. In some embodiments, the first wall 28 is configured to havetherapeutic benefits (pharmacologic, healing, and/or in-growthproperties) as described elsewhere herein. The second wall 30 mayadditionally and/or alternatively be configured to have a therapeuticeffect (pharmacologic, healing, and/or in-growth properties).Additionally, the thickness of the implant in certain locations isvariable to add cushioning to the implant as well as to provide jointspacing. In certain embodiments, the material is not variable inthickness, but provides the same cushioning and/or joint spacing for thebones of the joint. The central region in the embodiment of FIG. 14 isthicker material to add at least one of: cushioning, buffering, jointspace, restore cushioning, and to respond to clinical need.

Any of the balloons described herein with regard to any of the figuresmay add cushioning, padding, strength, durability, flexibility, or anyother aspect noted herein, and need not be a chamber per se, nor beinflatable per se. Rather they are merely distinguishable in certainembodiments from the walls which are on either side of them incomposition or function or both. In some embodiments, the balloon andits interior is not materially different in composition or function fromone of the walls. In some embodiments, they are not materially differentin composition or function from either of the walls.

FIGS. 15A, 15B, and 15C show several views of an embodiment of animplant which has no definable chamber, rather the material of theimplant itself provides the cushion to the bones of the joint (atleast). The implant in 15A, 15B, and 15C is generally H or V-shaped,having a slot 26 b that is significantly smaller than as shown otherembodiments (for example FIGS. 3, 4, 5, 6A, 6B, 7, 14). In certainembodiments, an implant shaped generally like FIGS. 15A, 15B, and 15 cmay comprise a chamber which, if the implant were shown in crosssection, may comprise a different material than the wall of the implantitself, or may be the same material but with different geometric orchemical or physical properties, as noted herein. FIGS. 15A, 15B, and15C depict an embodiment of the knee implant 20 having appendages 4 a, 4b, 4 c, 4 d and tabs 10 a, 10 b, 10 c, 10 d, 10 e, 10 f, 10 g, 10 h andincluding slots 26 a, 26 b to accommodate ligaments of the knee joint.Couplers as described elsewhere herein may be used to couple the implant20 to the distal femur. In some embodiments, there may only tabs, onlyholes, or only appendages, or combinations thereof. In some embodiments,there may be other ways to couple the implant to the distal femur, asdescribed elsewhere herein (sutures, drawstrings, skirts, glue, etc). Insome embodiments, the couplers create holes (not shown) when the implantis placed against the distal femur. In some embodiments, the holes arepre-formed in the appendage prior to implantation. In some embodiments,the holes are reinforced as described elsewhere herein. As shown here,the appendages in some embodiments are different in shape and/or size toaccommodate the differences in condyle size and/or shape. For examplethe medial condyle tends to be larger than the lateral condyle, and thusappendage 4 d that is intended to wrap over the medial condyle may belonger and/or wider than the appendage 4 c intended to wrap over thelateral condyle. The slots may be different in shape and/or size and/orposition to accommodate the ligaments and/or tendons of the joint orother structures and functions of the joints of the knee, and to allowfor placement of the implant with minimal disturbance (cutting,manipulation, for example) of the joint components such as tendons,ligaments, and other soft or hard tissues. For example, slot 26 a isshaped and positioned to accommodate the cruciate ligaments of the knee,at least. The thickness of the implant in certain locations is variableto add cushioning to the implant as well as to provide joint spacing. Incertain embodiments, the material is not variable in thickness, butprovides the same cushioning and/or joint spacing for the bones of thejoint.

FIG. 16 depicts a knee implant embodiment that is generally H orV-shaped, having a slot 26 b that is significantly smaller than otherembodiments, and in this embodiment is effectively replaced with a tab10 i at the same location (e.g. 10 i). FIG. 16 depicts an embodiment ofthe knee implant 20 having appendages 4 a, 4 b, 4 c, 4 d and tabs 10 a,10 b, 10 c, 10 d, 10 e, 10 f, 10 g, 10 h, 10 i and including a slots 26a to accommodate ligament(s) of the knee joint. Couplers as describedelsewhere herein may be used to couple the implant 20 to the distalfemur. Contour lines 54 a, 54 b, for example, are also depicted in FIG.16, however these are not necessarily significant other than to showcontour of parts of the implant 20, although they may be in the casewhere a mesh is provided in the implant. In some embodiments, there mayonly tabs, only holes, or only appendages, or combinations thereof. Insome embodiments, there may be other ways to couple the implant to thedistal femur, as described elsewhere herein (sutures, drawstrings,skirts, glue, etc). In some embodiments, the couplers create holes (notshown) when the implant is placed against the distal femur. In someembodiments, the holes are pre-formed in the appendage prior toimplantation. In some embodiments, the holes are reinforced as describedelsewhere herein. As shown here, the appendages in some embodiments aredifferent in shape and/or size to accommodate the differences in condylesize and/or shape. For example the medial condyle tends to be largerthan the lateral condyle, and thus appendage 4 d that is intended towrap over the medial condyle may be longer and/or wider than theappendage 4 c intended to wrap over the lateral condyle. The slot 26 amay be different in shape and/or size and/or position to accommodate theligaments and/or tendons of the joint or other structures and functionsof the joints of the knee, and to allow for placement of the implantwith minimal disturbance (cutting, manipulation, for example) of thejoint components such as tendons, ligaments, and other soft or hardtissues. For example, slot 26 a is shaped and positioned to accommodatethe cruciate ligaments of the knee, at least. The thickness of theimplant in certain locations is variable to add cushioning to theimplant as well as to provide joint spacing. In certain embodiments, thematerial is not variable in thickness, but provides the same cushioningand/or joint spacing for the bones of the joint. In certain embodiments,an implant shaped generally like FIG. 16 may or may not comprise achamber which, if the implant were shown in cross section, may comprisea several materials which may be the same as or different from any wallof the implant itself, or may be the same material but with differentgeometric or chemical or physical properties, as noted herein.

FIG. 17 depicts a knee implant embodiment similar to FIG. 16 which showsa posterior view including the location(s) 50 a-50 d where a fillmaterial such as cement may be placed. The fill material may be added inany one location 50 a, 50 b, 50 c, or 50 d, or added in several oflocations 50 a, 50 b, 50 c, and 50 d or likewise be added anywhere onthe first or second wall of the implant which contacts the first,second, and/or third bone. The fill material may be used to both cushion(as do balloons 6 in other figures) and/or secure the device to the bonein the case of a bone cement or a combination of these functions. In thecase where the cement is used as the fill material, the cement may beused in an element that may or may not have any, some, or all of tabs 10a-10 i. The cushion, thus can act as a coupler (fixation element) and/oras a cushion and/or spacer for the joint bones. The cushion (whether afill material such as cement or another material) may also be placedadjacent to a first wall or second wall, and not necessarily betweensaid first wall and second wall.

FIG. 18 is an anterior-posterior view of an embodiment of the implant 20attached to a knee model. The implant here comprises chambers 52 a, 52b, 53 c, at least (in this case, nano-inflated air pockets). Althoughsparsely shown in this embodiment, the frequency, size, etc. could beadapted to smaller chambers, larger chambers, more frequent chambers,more concentrated in particular areas of the implant, less concentratedin particular areas of the implant, or similarly adjusted. The chamberscan be diffuse, of any size, containing compressible gas (air), cells,pharmacologics, liquids, beads, metals, or other materials as notedherein.

FIG. 19 depicts an implant 20 which is more squarely cut for interfacewith a femur, for example, which has been cut square such as is done incertain total knee arthroplasty procedures. The implant in thissituation may comprise a polymer alone (of soft or hard durometer)and/or metal. The walls may be contiguous or include a chamber that isoptionally filled or fillable as noted herein. Although tabs are shownin FIG. 19, these are optional in embodiments where another attachmentelement (fixation element) is used such as cement or a metal pin orscrew or snap through an appendage of the device.

FIGS. 20A and 20B depict a knee implant embodiment that is generallyV-shaped or Y-shaped, and in this embodiment the slot 26 b of otherembodiments, or the tab 10 i of other embodiments is effectivelyreplaced with an appendage 4 e at the same location. FIG. 20A depicts anembodiment of the knee implant 20 having appendages 4 c, 4 d, and 4 eand holes 8 a (not shown, in FIG. 20B), 8 b (not shown, in FIG. 20B), 8c (not shown, in FIG. 20B), 8 d, 8 e, 8 f, 8 g, 8 h, 8 i, (not shown,substantially similarly positioned as 8 e on the same edge as 8 a-8 c ofFIG. 20A), 8 j (not shown, substantially similarly positioned as 8 d onthe same edge as 8 a-8 c of FIG. 20A), and including a slot 26 a toaccommodate ligament(s) of the knee joint. Couplers as describedelsewhere herein may be used to couple the implant 20 to the distalfemur through slots 8 a-8 j. Contour lines are also depicted in FIGS.20A and 20B, however these are not necessarily significant other than toshow contour of parts of the implant 20, although they may be in thecase where a mesh is provided in the implant. In some embodiments, theremay only tabs, only holes, or only appendages, or combinations thereof.In some embodiments, there may be other ways to couple the implant tothe distal femur, as described elsewhere herein (sutures, drawstrings,skirts, glue, etc). In some embodiments, the tabs comprise holes. Insome embodiments, the couplers create holes (not shown) when the implantis placed against the distal femur. In some embodiments, the holes arewithin the peripheral rim of the knee implant. In some embodiments, theholes are within the region of the intercondylar notch medially and/orlaterally. In some embodiments, the holes are through the polymer. Insome embodiments, the holes are through a reinforced rim. In someembodiments, the holes are pre-formed in the appendage prior toimplantation. In some embodiments, the holes are reinforced as describedelsewhere herein. As shown here, the appendages in some embodiments aredifferent in shape and/or size to accommodate the differences in condylesize and/or shape. For example the medial condyle tends to be largerthan the lateral condyle, and thus appendage 4 d that is intended towrap over the medial condyle may be longer and/or wider than theappendage 4 c intended to wrap over the lateral condyle. The slot 26 amay be different in shape and/or size and/or position to accommodate theligaments and/or tendons of the joint or other structures and functionsof the joints of the knee, and to allow for placement of the implantwith minimal disturbance (cutting, manipulation, for example) of thejoint components such as tendons, ligaments, and other soft or hardtissues. For example, slot 26 a is shaped and positioned to accommodatethe cruciate ligaments of the knee, at least. The thickness of theimplant in certain locations is variable to add cushioning to theimplant as well as to provide joint spacing. In certain embodiments, thematerial is not variable in thickness, but provides the same cushioningand/or joint spacing for the bones of the joint. In certain embodiments,an implant shaped generally like FIG. 20A or 20B may or may not comprisea chamber which, if the implant were shown in cross section, maycomprise a several materials which may be the same as or different fromany wall of the implant itself, or may be the same material but withdifferent geometric or chemical or physical properties, as noted herein.As shown in FIGS. 20A and 20B, thickness of between the first wall (partconfigured to touch the femur condyle) and the second wall (partconfigured to touch the tibia), is shown for example in the slot 26 a(which may be called a notch herein), thus showing a side wall asdescribed elsewhere herein to provide the thickness to the implant atthe condyle(s). This thickness may be a result of a thickness of amaterial of the implant (as in where the implant comprises a compliantpolymer), or due to an inflation of a balloon that resides between thefirst wall and the second wall and the side wall. In some embodiments,the implant comprises a Dyneema® mesh. The implant may comprise Dyneema®fiber. In some instances, the implant comprises Dyneema Purity® fiber.In some embodiments, the implant comprises a Dyneema Purity® UG fiber.In some embodiments, the implant comprises a Dyneema Purity® VG fiber.The implant may comprise a fiber. The implant may comprise apolyethylene. The implant may comprise a polyethylene fiber.

In all descriptions provided herein of the dual compartment implant, theimplant may instead be configured to couple to or emerge from the tibiaand/or patella. In all descriptions provided herein of the dualcompartment implant, the implant may instead be configured to couple tothe tibia. It is the intention and understanding that the implant issuited for this purpose in certain embodiments with adjustments toaccount for dimensional differences of the tibia. Most descriptionsprovided herein are directed to embodiments coupling the implant to thefemur, however, this is primarily for ease of description andcontinuity, and does not preclude embodiments wherein the implant iscoupled to the tibia. Likewise, as noted elsewhere herein, there areembodiments where the implant may be coupled to two bones (at least),for example to both a tibia and a femur.

To be clear, in some embodiments, there is no chamber in the implant. Insuch an embodiment, the implant may have a single composition throughoutthe implant, and shaped as noted herein with attachment features asnoted herein.

In some embodiments, the implant is a single layer polymer and has avariable thickness which is dependent or predicated upon the patientmorphology or anatomy. Preferably, the implant thickness ispredetermined based on a measurement of each patient's particularmorphology. The measurements can be from MRIs, CT Scans, X-Rays, and/orarthroscopic inspection and/or through palpation or patient experience.Since a patients joint surface may not be perfectly smooth, the implantmay be made with variable thicknesses or contours so that the undersideor bone engaging side of the implant fills in any surface anomalies onthe patients' bone or cartilage surface. The bone or femur engagingsurface may comprise peaks and troughs. Living cells as mentioned may beimposed in between (and/or provided in or with the implant) troughs ofthe implant surface while the surface areas of prominence (the peaks ofthe surface) may be used for at least one of: space validation,traction, and cell protection. Pharmaceuticals may be coated on the boneengaging surface prior to, during or subsequent to implantation.

The joint space engaging side of the implant may be smooth with notexture or contours. In some embodiments, the bone engaging surface andthe articulating surface have the same profile along any givendimensioned reference line as measured by the radius of curvature foreach surface. In a particular embodiment, the underside or bone engagingside is adapted to fit and/or engage a patients existing anatomy. Inanother particular embodiment, the implant is of a thickness that fitsinto joint capsule without the need to make room in the joint by theremoval of a patient's existing anatomy.

FIG. 21A depicts an embodiment of the implant 20 which has a main body301 which hugs both the medial and lateral condyles and has no balloon.In some embodiments, the main body 301 may extend along the metathesis,epiphysis and/or diaphysis of the femur. The implant 20 may be designedto fit or hug the articulating end of a left femur and accommodateligaments in slot 26 a. Articulating surface 201 engages the joint spaceand underside surface 202 is a bone engaging surface. In preferredembodiments, the bone engaging surface is the surface that engages thefemur, natural cartilage or remaining cartilage that is present on theend of the femur. The implant may be inserted into the capsule of theknee. Upon insertion of the implant into a right knee joint, appendage 4d will expand into the medial portion of the capsule or joint andappendage 4 c will expand into the lateral portion of the capsule orjoint. Upon insertion of the implant into a left knee joint or capsule,appendage 4 d will expand into the lateral portion of the capsule orjoint and appendage 4 c will expand into the medial portion of thecapsule or joint. Appendage 4 e is designed to hug or engage an anteriorportion of a femur and may be coextensive with appendages 4 c and 4 d.In some embodiments, the articulating surface of appendage 4 e isdesigned to articulate relative to a patella. This FIG. 21A shows animplant with pre-fabricated holes 18 a, 18 b and 18 c. Thepre-fabricated holes can be used in combination with a coupling orattachment means as described herein. In some embodiments, the implanthas no prefabricated holes (not shown).

FIG. 21B shows an embodiment of implant 20 having a rim 101circumscribing the implant including a lateral portion of the rim 104and a medial portion of the rim (not shown). The rim 101 may extendand/or define the periphery of the implant. In some embodiments, the rimmay be made of the same or different material as the implant and mayextend along the metathesis, epiphysis and/or diaphysis of the femur.The rim may be filleted. The rim may have a variable fillet. FIG. 21Bdepicts the rim 101 having an outer most peripheral edge 102 and aninner boundary 103. The distance between the outer most peripheral edge102 and an inner boundary 103 can be of variable lengths. Generally, thedistance between the outer most peripheral edge 102 and an innerboundary 103 is 1.0 to 3.5 times the thickness of the implant. Mostpreferably, the distance between the outer most peripheral edge 102 andan inner boundary 103 is 1.5 to 2.5 times the thickness of the implant.For example, the distance between the outer most peripheral edge 102 andan inner boundary 103 is 0.5 mm, 0.6 mm, 0.7 mm, 0.8 mm, 0.9 mm, 1.0 mm,1.1 mm, 1.2 mm, 1.3 mm, 1.4 mm, 1.5 mm, 1.6 mm, 1.7 mm, 1.8 mm, 1.9 mm,2.0 mm, 2.1 mm, 2.2 mm, 2.3 mm, 2.4 mm, 2.5 mm, 2.6 mm, 2.7 mm, 2.8 mm,2.9 mm, 3.0 mm, 3.1 mm, 3.2 mm, 3.3 mm, 3.4 mm, 3.5 mm, 3.6 mm, 3.7 mm,3.8 mm, 3.9 mm, 4.0 mm, 4.1 mm, 4.2 mm, 4.3 mm, 4.4 mm, 4.5 mm, 4.6 mm,4.7 mm, 4.8 mm, 4.9 mm, or 5.0 mm. The rim 101 may extend around all orpart of the periphery of the implant. Pre-fabricated holes such as 18 cand 18 b may be fabricated in the rim 101 (not shown) and such holes maybe used to facilitate anchoring of the implant. The implant rim 101 maybe of variable thickness and construction independent of the rest of theimplant. In some embodiments, the rim 101 may be of a different materialthan the rest of the implant. In other embodiments, the rim 101 may becontoured or textured, such as fashioned with protuberances.

FIG. 22A shows a cross-sectional cutaway along RLM of FIG. 27 includingthe bone engaging surface 202 and joint articulating surface 201 whichare also depicted. The thickness of the implant, which can be defined bythe bone engaging surface 202 and the joint articulating surface 201 canbe the same throughout the implant. In other words, the implantthickness can be the distance between the bone engaging surface 202 andthe joint articulating surface 201. The implant thickness can beadjusted according to patient anatomy, physiology and need. In apreferred aspect, the thickness is 0.5 mm thick. In other aspects, thethickness can be from 0.01 mm to 5 mm. In some instances, the distancecan be 0.02 mm, 0.03 mm, 0.04 mm, 0.05 mm, 0.06 mm, 0.07 mm, 0.08 mm,0.09 mm, 0.1 mm, 0.2 mm, 0.3 mm, 0.4 mm, 0.5 mm, 0.6 mm, 0.7 mm, 0.8 mm,0.9 mm, 1.0 mm, 1.1 mm, 1.2 mm, 1.3 mm, 1.4 mm, 1.5 mm, 1.6 mm, 1.7 mm,1.8 mm, 1.9 mm, 2.0 mm, 2.1 mm, 2.2 mm, 2.3 mm, 2.4 mm, 2.5 mm, 2.6 mm,2.7 mm, 2.8 mm, 2.9 mm, 3.0 mm, 3.1 mm, 3.2 mm, 3.3 mm, 3.4 mm, 3.5 mm,3.6 mm, 3.7 mm, 3.8 mm, 3.9 mm, 4.0 mm, 4.1 mm, 4.2 mm, 4.3 mm, 4.4 mm,4.5 mm, 4.6 mm, 4.7 mm, 4.8 mm, 4.9 mm, or 5.0 mm. The thickness of theimplant may be made to a custom fit for a particular patient's knee(left or right). For example, the measurements for the custom fit can beparticular such as 1.025 mm, 1.050 mm, or 1.075 mm. The thickness insome embodiments may vary throughout the implant to accommodate aparticular patient's anatomy. FIG. 22B shows a medial cutaway of theimplant along RLL (also shown in FIG. 27). In some embodiments, thethickness of the implant has an average consistency. In someembodiments, the thickness of the implant may vary to accommodatecertain features of a patient's anatomy. In a preferred aspect, theaverage thickness of the implant is consistent throughout the main bodyof the implant.

FIG. 23 is a posterior view of the implant. Appendage 4 d may bedifferent from appendage 4 c.

FIG. 24 shows a side view of the implant 20 having a bridge support 501.The bridge support 501 may be a thickened flange on both the medial andlateral sides of the implant to provide stability and contact surfacefor adhering to the bone and or cartilage. The bridge support 501 may becoextensive with the main body of the implant. The bridge support 501may be made of the same or different material as the implant and mayextend along the metathesis, epiphysis and/or diaphysis of the femur. Ina preferred embodiment, prefabricated holes 18 b and 18 c areconstructed in the bridge support 501.

FIG. 25 depicts an implant for a right knee such that appendage 4 d hugsa medial condyle of a femur and appendage 4 c hugs a lateral condyle ofa femur.

FIG. 26 depicts an implant showing an underside or bone engaging surface202 of an implant 20. The bone engaging surface 202 may have the sameradius of curvature profile as the articulating surface 201. However,the bone engaging surface 202 may have microfeatures such as indents,divits, contours, grooves, vacuoles or other irregularities to allow forbone in-growth and fixation of the implant to the bone and/or remainingcartilage.

FIG. 27 shows an isometric view of an implant for a left knee. Line RLLis a dimensioned reference line on the medial side of implant 20 and RLMis a dimensioned reference line on the lateral side of implant 20.Dimensioned reference line RLM extends from an anterior part of theimplant periphery 401 to a posterior part of the implant periphery 402.Dimensioned reference line RLL extends from an anterior part of theimplant periphery 401 to a posterior part of the implant periphery 402.The dimensional measurements along RLL may be different from those alongRLM. Not shown is an implant design for a right knee with dimensionedreference lines. Dimensional measurements for an implant for a rightknee may be the same or different than those for a left knee.

FIG. 28 depicts a posterior view of implant 20.

FIG. 29 depicts an isometric view of an implant having a dimensionedreference line RLC. Dimensioned reference line RLC may extend from alateral portion 106 of appendage 4 d to a medial portion 105 ofappendage 4 c. The dimensional measurements along RLC may be the same ordifferent for appendage 4 d and appendage 4 c. In one embodiment, theradial curvature profile for the appendage hugging and/or engaging themedial condyle may be different than the radial curvature profile forthe appendage hugging and/or engaging the lateral condyle alongdimensioned reference line RLC. Curvature profiles along dimensionedreference line RLC may be different for implants fabricated for rightknees than curvature profiles along dimensioned reference line RLC forimplants fabricated for left knees.

Example 1

Radius of curvature measurements can be taken along the cutaway profilesof the implant. An implant was designed for a sample left femur. Modelswere created from a 3D model of a SawBones femur. A sketch line wascreated along the distal end of the femur that follows the articularcartilage. After an acceptable outline was created, a surface of thefemur was copied from within the outline. The next step was to thickenand extrude a single polymer layer of thermoplastic to a 1.0 mmthickness. This particular implant design had a filleted rim which wasnot included in the radius of curvature measurements. The radius ofcurvature was measured for both the joint articulating surface and thebone engaging surface. The segment lengths or arc lengths used for thebasis of measurement for the joint articulating surface of the implantwere 10.33 mm. The segment lengths or arc lengths used for the basis ofmeasurement for the bone engaging surface were 10 mm. The segmentslengths were taken along a dimensioned reference line similar to that ofline RLM of FIG. 27 starting from an anterior point to a posterior pointon the implant periphery. The segments along the joint articulatingsurface were numbered from 1-11 wherein the first segment was measuredstarting from an anterior point on the implant periphery, not includinga filleted rim area. The segments along the bone engaging surface werenumbered from 12-22 wherein the twelfth segment was measured startingfrom an anterior point on the implant periphery, not including afilleted rim area. Segments or arc lengths were measured and the radiusof curvature for each arc length is provided in Table 1 and Table 2.

TABLE 1 Segments - Radius of Curvature articulating surface Value(radius in mm) Segment 1 183.17 Segment 2 26.48 Segment 3 26.53 Segment4 23.28 Segment 5 38.31 Segment 6 65.30 Segment 7 38.63 Segment 8 30.74Segment 9 21.76 Segment 10 15.36 Segment 11 51.39

TABLE 2 Segments - bone Radius of Curvature engaging surface Value(radius in mm) Segment 12 141.91 Segment 13 26.58 Segment 14 23.89Segment 15 22.05 Segment 16 39.23 Segment 17 60.95 Segment 18 39.84Segment 19 28.71 Segment 20 19.29 Segment 21 14.67 Segment 22 34.7

The results from Table 1 as graphed is shown in FIG. 30 and the resultsfrom Table 2 as graphed are shown in FIG. 31. FIG. 30 and FIG. 31demonstrate that the radius of curvature profiles for both thearticulating surface and the joint engaging surface are very similar.The similarity has to do in part with the consistent thickness of theimplant and/or the average thickness of the implant.

In some embodiments, the implant is configured such that the tabs and/orcouplers of the implant couple to the bone where there is no naturalcartilage. In some embodiments, the implant may be adapted by thesurgeon at the time of surgery such that the tabs are positioned wherethere is no natural cartilage.

In some embodiments, the implant comprises a tab and a hook that couplesto the tab by wrapping around a component of the knee and securing thetab to the hook. In some embodiments, the implant comprises a tab and ahook that couples to the tab by wrapping around a condyle of the kneeand securing the tab to the hook. In some embodiments, the implant isconfigured to wrap around a condyle of the knee and to secure a firstappendage to a second appendage of the implant. In some embodiments theappendages are secured by couplers described herein. In someembodiments, the implant is pre-formed to fit to the condyle in such awrapping manner.

In some embodiments, the implant comprises a methymethacrylate what isplaced into a balloon chamber that fits into a bone hole. Such anembodiment would generally fix the implant to the bone once themethymethacrylate cures to a solid.

In some embodiments, the implant can be anchored with generic availablesutures and suture anchors fixing and positioning material to bone withproper tensioning.

Ingrowth Features

In addition to the general ingrowth that may occur based on the implantfeatures described herein, the implant undersurface (adjacent the femur)may comprise an ingrowth matrix. In some embodiments, at least a portionof the implant adjacent to the femur comprises bone ingrowth materials.Such an implant can be attached by a series of tabs with or withoutholes, using screws, rivots, stabilizers, staples, tacks, or Sutures andsuture anchors, for non-limiting example. The polymer of the implantsubstitutes for periosteum when the implant comprises livingchondrocytes (e.g. Carticel) as the ingrowth matrix on a surface of theimplant. The polymer of the implant substitutes for periosteum when theimplant comprises living chondrocytes (e.g. Carticel) as the ingrowthmatrix within an implant embodiment configured to reveal and/or releasesaid chondrocytes over time and/or upon implantation.

The bone ingrowth undersurface may be used for long term fixation of thetabs or rim. That is, whereas it is important for the surgery to securethe implant to the joint surface in the most desirable correctivelocation, it is also important in some embodiments to prepare theanatomic undersurface of bone by abraiding it, removing about 0.5 mm ofcortical bone so as to expose the underlying oxygen, blood, andnutrients of the patient to the undersurface of the implant that cangradually become incorporated into the limb bone. As this healing occursover the course of weeks and months to one year post operation, thelocalized tacking sites may become less relevant and potentially inert.Thus, in some embodiments, the implant may comprise a biodegradable(bioresorbable) polymer or other material. The couplers may additionallyand/or alternatively be biodegradable. Once the implant is in place, itwill serve to at least one of: pad defects, cushion the joint, andrestore the original damage to the joint components. The end goal is toapply minimally morbid treatment that will refurbish arthritic limbregions, leaving only the small skin scar and remote memory of thehealed physical mishap.

Undersurface implant materials may involve used of the art and sciencefrom Artelon or Gore-Tex research, as each has advantages andlimitations. Several implant options per joint damage area may beavailable to enjoy the primary surgeons manipulation to fit theclinically recovery requirements best.

In some embodiments the implant comprises an ingrowth patch on at leastone of the first portion configured to engage the femur, the secondportion configured to engage the second bone (whether the tibia or thepatella), the side portion, and the appendage. The ingrowth patch may beconfigured to encourage and/or promote tissue ingrowth, such as boneingrowth, for non-limiting example. The patch may be as large as theportion itself (whether the first portion the second portion, the sideportion, or the appendage) or may be smaller than the portion (such asin the shape of a strip or other shaped patch). The ingrowth patch maycomprise a surface irregularity or roughness. The ingrowth patch may beVelcro-like. In some embodiments the implant comprises an ingrowth patchon the first portion and/or the second portion, from (and in someembodiments including) a first appendage to a second appendage. In someembodiments, wherein the appendages loosen from attachment from the bone(by design and/or from wear and/or over time), the ingrowth patch aidsin securing the implant to the bone. In some embodiments, the ingrowthpatch comprises beads and/or bead-like elements attached to the implant.Such an ingrowth patch may be configured to simulate trabecular bonespace of a normally cancellous latticework. In some embodiments, thebeads are sintered beads of various sizes. In some embodiments, thebeads are sintered beads about 400 microns in size. With respect to beadsize, the term “about” can mean ranges of 1%, 5%, 10%, 25%, or 50%. Insome embodiments, the first bone and/or the second bone is roughened toacquire a bleeding bone to facilitate ingrowth. In some embodiments,tissue is removed to facilitate ingrowth.

The walls of the implant embodying features of the invention may becomposite structures. For example, the innermost layer may be imperviousto preclude escape of inflation or other filling media, a central layermay be porous or otherwise contain treatment or cell regenerationagents, and the outer layer may be a thin, but strong layer of athermoplastic, such as a thermoplastic polyurethane for non-limitingexample, which has microporosity sufficient to allow passage or egressof treatment or cell regeneration agents from the central layer (orsecond layer). The degree of microporosity to enable egress of treatmentor cell regeneration agents from the central layer is found in polymerlayers such as Chronoflex or Bionate 55. The external wall (and/or thebone engaging surface) of the implant may be coated and/or impregnatedwith a latticework of polymer that is surface sprayed or layered on theoutside (or bone engaging surface) of the implant to promote cartilagetissue regeneration. This most external surface coating may containliving chondrocytes (for example, as is provided in the Carticelprocedure by the Genzyme company), and/or may contain stem cells with orwithout directed gene mutations to enhance adherence of the coating tothe implant. The bone engaging surface may comprise peaks and troughs.The living cells may be imposed in between (and/or provided in the)troughs of the implant surface while the surface areas of prominence(the peaks of the surface) may be used for at least one of: spacevalidation, traction, and cell protection.

The implant embodying features of the invention may be used in a seriesof treatments wherein the first treatment involves use of autologous orminimally manipulated allograph interpositional tissues or xenograph,the second treatment involves the use of the same type of tissue addedto stem cells or chondrocytes and the third treatment involvingdeployment of the implant if the first two fail or are ineffective.

Pharmacologics and Therapeutic Agents

In some embodiments the implant may comprise vacuoles of pharmacologicsubstances. The vacuoles may be on a bone-engaging portion of theimplant. In some embodiments, the implant comprises bubbles comprisingan active substance such as a pharmacologic substance or other activesubstance. In some embodiments, the implant comprises spaces filled withan active substance such as a pharmacologic substance (pharmacologicagent) or other active substance (active agent). The implant may deliverby dissolution of the implant material (i.e. a biodegradable polymerwhich releases the active substance), and/or by release through pores ofthe implant (wherein the polymer is permeable to the active substance),and/or by fracture of the vacuole (or bubble, or space) by a catalystsuch as ultrasound or pressure or other fracturing catalyst. The implantmay deliver the active substance at a time after the actual implantingof the implant into the joint, for example an hour later, less than aday later, a day later, less than a week later, a week later, less thana month later, and/or a month later. In some embodiments, stem cellsthat are percolating in the bubble (or vacuole, or space) may bedelivered to the joint space (or a constituent of the joint) after theimplant is inserted into the joint. Active agents may, for non-limitingexample, include stem cells, growth factors, antibiotics, and/orviscolubricants. In some embodiments, the implant may comprise enzymeabsorptive ‘microscopic sponges’ that could be sucked out or evacuatedat or around the time of implant delivery to the joint. In someembodiments, the active substance comprises iatrigenically gene mutatedcells.

Patient Symptoms

Symptoms for the patient requiring an implant described herein mayinclude, for non-limiting example, osteoarthritis or rheumatoid or goutyarthritis.

Total Knee Arthroplasty (Dual Compartment):

Provided herein is an implant for placement on both condyles (medial andlateral) of the distal femur. In some embodiments, this is called a dualcompartment implant since it covers both condyles of the femur. Such animplant comprises at least one interior (or inflatable chamber), and insome embodiments comprises a plurality of inflatable chambers (orinteriors).

In some embodiments, the implant will cover the “H” distal femoralcartilage segment (made up of both femoral condyles and the trochleargroove in between). The implant may absorb diffuse force, endure themillions of annual cyclic loads of both knee joints (including thepatella-femur joint and the femur-tibia joints), along with rotationaland shear forces up to six times body weight, at least.

In some embodiments, the implant comprises attachment tabs or attachmentelements over the sides of both condyles medially and laterally. In someembodiments, the implant comprises attachment tabs or attachmentelements in the intercondylar notch (or slot). In some embodiments, theimplant comprises attachment tabs or attachment elements superiorly atthe distal end of the femur anteriorly. In some embodiments, posteriorreigns or suture-like lanyards cinch up the implant from inside theposterior intercondylar notch toward another connection site around thefemur.

The posterior of the knee can be difficult to access without disturbingjoint components (or in order to minimize such disturbance) such astendons, ligaments, etc. Thus, in some embodiments, the implantcomprises strings, reigns, lassos, and/or lanyards that may pass fromthe posterior of the implant via the intercondylar notch anteriorly tojoin with themselves and/or other coupling devices. These couplers maybe pre-coupled to the implant, and the implant and its couplers may beconfigured to be pulled (or cinched) from the anterior of the implantonce the implant is in its general location relative to the condyle inorder to finally position the implant about the condyle—in particular inorder to cinch the implant about the posterior of the condyle. Likewise,in some embodiments where the implant is pre-molded, the coupler asdescribed are adapted to move the implant to its final position withconformity to the condyle's posterior with minimal disturbance to thejoint structures at the joint's posterior (minimal cutting, minimalmoving, and or minimal detachment, for non-limiting example). In someembodiments at least a portion of the ligamentary structure of the kneeis spared.

Although this application focuses on the distal femur as it articulateswith the retropatellar and proximal tibial cartilages implants asdescribed generally herein may be also and/or alternatively be used inconjunction with the tibia and/or the patella. Furthermore, separateand/or connected implant components may be inserted to restore naturalfunction to the knee.

Coupling devices to be used as part of the dual compartment implant mayinclude any of those mentioned or described herein, for example. Suchcoupling devices may comprise at least one of strings (i.e.drawstrings), reigns, lassos, sutures, and lanyards. The strings,reigns. lassos, sutures, and/or lanyards may join with themselves and/orother coupling devices. The strings, reigns. lassos, sutures and/orlanyards may be directed not only into bone with or without anchors, butalso through ligaments, tendons or loose segments of cartilage that thesurgeon intends to preserve.

FIG. 1 depicts an embodiment of the implant 20 in a 2D view configuredfor dual condyle (distal femur) coverage. FIG. 1 depicts an embodimentof the knee implant 20 having appendages 4 a, 4 b, 4 c, 4 d, includingholes 8 a, 8 b, 8 c, 8 d and tabs 10 a, 10 b extending from a balloon 6and including slots 26 a, 26 b to accommodate ligaments (not shown) ofthe knee joint. Couplers as described elsewhere herein may be used tocouple the implant 20 to the distal femur. In some embodiments, theremay only tabs, only holes, or only appendages, or combinations thereof.In some embodiments, there may be other ways to couple the implant tothe distal femur, as described elsewhere herein (sutures, drawstrings,skirts, glue, etc). In some embodiments, the couplers create the holes 8a, 8 b, 8 c, 8 d, or other holes (not shown) when the implant is placedagainst the distal femur 24. In some embodiments, the holes arepre-formed in the appendage prior to implantation. In some embodiments,the holes are reinforced as described elsewhere herein. As shown here,the appendages in some embodiments be different in shape and/or size toaccommodate the differences in condyle size and/or shape. For examplethe medial condyle tends to be larger than the lateral condyle, and thusappendage 4 d that is intended to wrap over the medial condyle may belonger and/or wider than the appendage 4 c intended to wrap over thelateral condyle. Likewise, the slots may be different in shape and/orsize and/or position to accommodate the ligaments and/or tendons of thejoint or other structures and functions of the joints of the knee, andto allow for placement of the implant with minimal disturbance (cutting,manipulation, for example) of the joint components such as tendons,ligaments, and other soft or hard tissues. For example, slot 26 a isshaped and positioned to accommodate the cruciate ligaments of the knee,at least.

FIG. 2 depicts an embodiment of the knee implant 20 having appendages 4a, 4 b, 4 c, 4 d, including holes 8 a, 8 b, 8 c, 8 d and tabs 10 a, 10 bextending from a balloon 6 and including slots 26 a, 26 b to accommodateligaments of the knee joint as well as side views of the same kneeimplant. Couplers as described elsewhere herein may be used to couplethe implant 20 to the distal femur. In some embodiments, there may onlytabs, only holes, or only appendages, or combinations thereof. In someembodiments, there may be other ways to couple the implant to the distalfemur, as described elsewhere herein (sutures, drawstrings, skirts,glue, etc). In some embodiments, the couplers create the holes 8 a, 8 b,8 c, 8 d, or other holes (not shown) when the implant is placed againstthe distal femur. In some embodiments, the holes are pre-formed in theappendage prior to implantation. In some embodiments, the holes arereinforced as described elsewhere herein. As shown here, the appendagesin some embodiments are different in shape and/or size to accommodatethe differences in condyle size and/or shape. For example the medialcondyle tends to be larger than the lateral condyle, and thus appendage4 d that is intended to wrap over the medial condyle may be longerand/or wider than the appendage 4 c intended to wrap over the lateralcondyle. Shown in the embodiment depicted in FIG. 2 are the differenthole placements from the side view, showing the differences inpositioning of the holes to accommodate the differences in anatomicstructure and size of the condyles. Likewise, the slots may be differentin shape and/or size and/or position to accommodate the ligaments and/ortendons of the joint or other structures and functions of the joints ofthe knee, and to allow for placement of the implant with minimaldisturbance (cutting, manipulation, for example) of the joint componentssuch as tendons, ligaments, and other soft or hard tissues. For example,slot 26 a is shaped and positioned to accommodate the cruciate ligamentsof the knee, at least. Additionally, as shown in the side views of theembodiment shown in FIG. 2, the balloon has a first wall 28 adapted tobe adjacent the femur that is of a greater thickness than the secondwall 30. In some embodiments, the first wall 28 is configured to havetherapeutic benefits (pharmacologic, healing, and/or ingrowthproperties) as described elsewhere herein. The second wall 30 mayadditionally and/or alternatively be configured to have a therapeuticeffect (pharmacologic, healing, and/or ingrowth properties).

Nevertheless, differing thicknesses of the first wall 28 and the secondwall 30 are not necessarily required in order to impart the therapeuticbenefits (pharmacologic, healing, and/or ingrowth) described elsewhereherein. For example, FIG. 3 depicts an embodiment of the knee implant 20having appendages 4 a, 4 b, 4 c, 4 d, including holes 8 a, 8 b, 8 c, 8 dand tabs 10 a, 10 b extending from a balloon 6 and including slots 26 a,26 b to accommodate ligaments of the knee joint as well as side views ofthe same knee implant. Couplers as described elsewhere herein may beused to couple the implant 20 to the distal femur. In some embodiments,there may only tabs, only holes, or only appendages, or combinationsthereof. In some embodiments, there may be other ways to couple theimplant to the distal femur, as described elsewhere herein (sutures,drawstrings, skirts, glue, etc). In some embodiments, the couplerscreate the holes 8 a, 8 b, 8 c, 8 d, or other holes (not shown) when theimplant is placed against the distal femur. In some embodiments, theholes are pre-formed in the appendage prior to implantation. In someembodiments, the holes are reinforced as described elsewhere herein. Asshown here, the appendages in some embodiments are different in shapeand/or size to accommodate the differences in condyle size and/or shape.For example the medial condyle tends to be larger than the lateralcondyle, and thus appendage 4 d that is intended to wrap over the medialcondyle may be longer and/or wider than the appendage 4 c intended towrap over the lateral condyle. Shown in the embodiment depicted in FIG.3 are the different hole placements from the side view, showing thedifferences in positioning of the holes to accommodate the differencesin anatomic structure and size of the condyles. Likewise, the slots maybe different in shape and/or size and/or position to accommodate theligaments and/or tendons of the joint or other structures and functionsof the joints of the knee, and to allow for placement of the implantwith minimal disturbance (cutting, manipulation, for example) of thejoint components such as tendons, ligaments, and other soft or hardtissues. For example, slot 26 a is shaped and positioned to accommodatethe cruciate ligaments of the knee, at least. Additionally, as shown inthe side views of the embodiment shown in FIG. 3, the balloon has afirst wall 28 adapted to be adjacent the femur that is of approximatelythe same thickness than the second wall 30. In some embodiments, thefirst wall 28 is configured to have therapeutic benefits (pharmacologic,healing, and/or ingrowth properties) as described elsewhere herein. Thesecond wall 30 may additionally and/or alternatively be configured tohave a therapeutic effect (pharmacologic, healing, and/or ingrowthproperties).

FIG. 4A depicts an embodiment of the knee implant 20 having appendages 4a-4 d including ten tabs 10 a-10 j extending from a balloon 6 andincluding a slot 26 a to accommodate components (such as ligaments orother tissues whether soft tissues, hard tissues, tendons, and/orothers) of the knee joint (not shown). The tabs 10 a-10 j are not shownwith holes in this embodiment, however if screws are used as couplers,such holes may be pre-drilled or formed in situ by the screws.Additionally and/or alternatively, staples or sutures may be used (asdescribed elsewhere herein) in order to couple the implant to the bone(femur, for example). Other couplers as described elsewhere herein mayalso and/or alternatively be used in this coupling process. Furthermore,the number of tabs may be fewer or greater than the ten depicted inorder to achieve optimal placement and coupling to the bone. Forexample, FIG. 4B depicts an embodiment of the knee implant 20 havingappendages 4 a-4 d including eight tabs 10 a-10 h extending from aballoon 6 and including a slot 26 a to accommodate components (such asligaments or other tissues whether soft tissues, hard tissues, tendons,and/or others) of the knee joint (not shown).

FIG. 5 depicts an embodiment of the knee implant 32 curved to simulatecurvature about the condyles of a femur, the implant having appendages 4a-4 d extending from an uninflated balloon (not shown) and includingslots 26 a, 26 b to accommodate components (such as ligaments or othertissues whether soft tissues, hard tissues, tendons, and/or others) ofthe knee joint (not shown). The implant may comprise additionalcurvatures and/or slots to accommodate other ligaments and/or tissues.In some embodiments, the implant is configured to conform about varioushard and/or soft tissues of the joint, such as bone, ligaments, tendons,etc. In some embodiments, the balloon is inflated once the implant ispositioned within the joint. In other embodiments, the balloon ispartially inflated prior to being positioned within the joint. In otherembodiments, the balloon is at least partially inflated prior to beingpositioned within the joint. In some embodiments, the balloon is fullyinflated prior to being positioned within the joint. In someembodiments, the implant is configured to allow an operator to adjustthe amount of balloon inflation in situ (whether by adding inflationmedium or removing inflation medium, or both, or neither). Couplers asdescribed elsewhere herein may be used to couple the implant 32 to thedistal femur.

FIG. 6A depicts a top-down view of an embodiment of the knee implant 32curved to simulate curvature about the condyles of a femur, the implanthaving appendages 4 a-4 d extending from two inflated balloons 6, 34 andincluding a slot 26 a to accommodate components of the knee joint. FIG.6B depicts a bottom-up or anterior oblique view of the same embodimentof the knee implant 32 curved to simulate curvature about the condylesof a femur, the implant having appendages 4 a-4 d extending from twoinflated balloons 6, 32 and including a slot 26 a to accommodatecomponents of the knee joint. Couplers as described elsewhere herein maybe used to couple the implant 32 to the distal femur. As shown in FIGS.6A and 6B, the appendages 4 a-4 d in some embodiments are different inshape and/or size to accommodate the differences in condyle size and/orshape. For example the medial condyle tends to be larger than thelateral condyle, and thus appendage 4 d that is intended to wrap overthe medial condyle may be longer and/or wider than the appendage 4 cintended to wrap over the lateral condyle. Likewise, the dimensions ofthe balloon 34 that is adapted for placement over the medial condyle maybe a different shape and/or size than the balloon 6 over the lateralcondyle (the medial condyle being larger, thus the balloon 34 may belarger for that location) Alternatively and/or additionally, asdescribed elsewhere herein, for various reasons such as injury,realignment needs, injury, etc, there may be a need for morereconstruction of one condyle than needed for the other, thus theinflation medium might be different in one balloon (or a portionthereof) than in the other balloon (or another chamber within the sameballoon), or there may be need for a different shaped balloon in onelocation than in another location. Embodiments provided herein canaccommodate these requirements based on materials of fillers,appendages, balloons, walls, and dimensions and chamber options of theimplant and its components.

FIG. 7 depicts a top-down view of an embodiment of the knee implant 32curved to simulate curvature about the condyles of a femur, the implanthaving appendages 4 a-4 d extending from an inflated balloon 6 andincluding slots to accommodate components of the knee joint. Couplers asdescribed elsewhere herein may be used to couple the implant 32 to thedistal femur. As shown here, the appendages 4 a-4 d in some embodimentsare different in shape and/or size to accommodate the differences incondyle size and/or shape. For example the medial condyle tends to belarger than the lateral condyle, and thus appendage 4 d that is intendedto wrap over the medial condyle may be longer and/or wider than theappendage 4 c intended to wrap over the lateral condyle. Likewise, thedimensions of the portion of the balloon that is adapted for placementover the medial condyle may be a different shape and/or size than theportion of the balloon over the lateral condyle (the medial condylebeing larger, thus the balloon may be larger for that location)Alternatively and/or additionally, as described elsewhere herein, forvarious reasons such as injury, realignment needs, injury, etc, theremay be a need for more reconstruction of one condyle than needed for theother, thus the inflation medium might be different in a portion orchamber of an implant embodiment having a plurality of inflationchambers in a single balloon, or there may be need for a non-symmetricballoon. Embodiments provided herein can accommodate these requirementsbased on materials of fillers, appendages, balloons, walls, anddimensions and chamber options of the implant and its components.

FIG. 8 depicts a side view of an embodiment of the knee implant 32curved to simulate curvature about at least one condyle of a femur, theimplant having appendages 4 b, 4 d extending from an uninflated balloon(not shown). This depiction covers the maximum anticipated distalfemoral contour; other iterations may be smaller, or shorter coveringlimited areas of the circumference of the femoral curvatures.

FIG. 9A depicts a side view of an embodiment of the knee implant 20curved about at least one condyle 22 of a femur 24, the implant 20having appendages 4 b, 4 d extending from an uninflated or minimallyinflated balloon 6. In this view, the knee is positioned essentially inextension (straight), showing the tibia 36, fibula 38, and patella 40 ofthe knee. Note that although there would be other joint structures andknee structures in a true depiction of an implant positioned in theknee, this view of the implant and bones is greatly simplified for easeof understanding of the implant and the joint relative (and approximate)positions and placement. Couplers as described elsewhere herein may beused to couple the implant 20 to the distal femur 24 and/or the condyle22 thereof (in this image the medial condyle, at least since it isprimarily a one-side view of the joint and implant). For the sake ofsimplicity FIG. 9A and the implant embodiment depicted show of the femurwith opposition to the other surfaces of both knee joints (between femurand tibia, and femur and patella), the areas of contact varyingaccording to activity, forces, and range of motion. Other implantiterations may apply to opposing surfaces.

FIG. 9B depicts a side view of an embodiment of the knee implant 20curved about at least one condyle 22 of a femur 24, the implant 20having appendages 4 b, 4 d extending from an inflated balloon 6. In thisview, the knee is positioned essentially in extension (straight),showing the tibia 36, fibula 38, and patella 40 of the knee. Note thatalthough there would be other joint structures and knee structures in atrue depiction of an implant positioned in the knee, this view of theimplant and bones is greatly simplified for ease of understanding of theimplant and the joint relative (and approximate) positions andplacement. Couplers as described elsewhere herein may be used to couplethe implant 20 to the distal femur 24 and/or the condyle 22 thereof (inthis image the medial condyle, at least since it is primarily a one-sideview of the joint and implant). In FIG. 9B wherein the balloon isinflated, as compared to FIG. 9A wherein the balloon is not inflated oris minimally inflated, the balloon second wall 30 is closer to and/orcontacting the tibial plateau 42 (articular surface) when the balloon 6is inflated. Likewise, FIG. 9C depicts a side view of an embodiment ofthe knee implant 20 curved about at least one condyle 22 of a femur 24,the implant 20 having appendages 4 b, 4 d extending from an inflatedballoon 6 and having couplers 44 a, 44 b (which may be, for non-limitingexample, staples or screws) coupling the appendages 4 b, 4 d to thefemur. In this view, the knee is positioned essentially in extension(straight), showing the tibia 36, fibula 38, and patella 40 of the knee.Where the inflated balloon as seen in FIG. 9B may fill in existingpathologic defects of the joint surface, the medium of inflated andspecific balloon location and durometry with the material of the implantmay also be constructed so as to force the bones opposed, e.g. the femurand tibia, into a more natural limb alignment such as six (6) degreesvalgus. However, if the patient being treated has variations from normalin the affected knee as illustrated by examining and measuring theopposite normal side, then the implant inflation and pressures orballoon location may be adjusted from the population norms thuscustomizing this implant to the clinical case under consideration.Fixation devices may be appropriately applied at various knee range ofmotion intervals from full extension (zero degrees) to full flexion(usually 135 degrees) as the knee is adjusted and the implant securedunder anesthesia.

FIG. 10A depicts a side view of an embodiment of the knee implant 20curved about at least one condyle 22 of a femur 24, the implant 20having appendages 4 b, 4 d extending from an inflated balloon 6 andshowing the inflation medium 46 moved anteriorly toward the patella 40when the knee joint is slightly flexed. Likewise, FIG. 10B depicts aside view of an embodiment of the knee implant 20 curved about at leastone condyle 22 of a femur 24, the implant 20 having appendages 4 b, 4 dextending from an inflated balloon 6 and having couplers 44 a, 44 b(which may be, for non-limiting example, staples or screws) coupling theappendages 4 b, 4 d to the femur 24 and showing the inflation medium 46moved anteriorly toward the patella 40 when the knee joint is slightlyflexed.

In all descriptions provided herein of the dual compartment implant, theimplant may instead be configured to couple to or emerge from the tibiaand/or patella. In all descriptions provided herein of the dualcompartment implant, the implant may instead be configured to couple tothe tibia. It is the intention and understanding that the implant issuited for this purpose in certain embodiments with adjustments toaccount for dimensional differences of the tibia. Most descriptionsprovided herein are directed to embodiments coupling the implant to thefemur, however, this is primarily for ease of description andcontinuity, and does not preclude embodiments wherein the implant iscoupled to the tibia. Likewise, as noted elsewhere herein, there areembodiments where the implant may be coupled to two bones (at least),for example to both a tibia and a femur.

Patch

Some embodiments of the implant are configured to repair isolatedlesions wherein osteochondral defects as in osteonecrosis create cratersin the cartilage that need ‘filling in’ with a patch. Various sizelesions of cartilage defects can be accommodated by the implantsprovided herein which may have balloons of at least one of: at mostabout 0.5 cm in diameter, at most about 0.75 cm in diameter, at mostabout 1 cm in diameter, at most about 1.25 cm in diameter, at most about1.5 cm in diameter, at most about 1.75 cm in diameter, at most about 2cm in diameter, at most about 2.25 cm in diameter, at most about 2.5 cmin diameter, at most about 2.75 cm in diameter, at most about 3 cm indiameter, at most about 3.25 cm in diameter, at most about 3.5 cm indiameter, at most about 3.75 cm in diameter, at most about 0.5 cm inlength along the longest length of the balloon, at most about 0.75 cm inlength along the longest length of the balloon, at most about 1 cm inlength along the longest length of the balloon, at most about 1.25 cm inlength along the longest length of the balloon, at most about 1.5 cm inlength along the longest length of the balloon, at most about 1.75 cm inlength along the longest length of the balloon, at most about 2 cm inlength along the longest length of the balloon, at most about 2.25 cm inlength along the longest length of the balloon, at most about 2.5 cm inlength along the longest length of the balloon, at most about 2.75 cm inlength along the longest length of the balloon, at most about 3 cm inlength along the longest length of the balloon, at most about 3.25 cm inlength along the longest length of the balloon, at most about 3.5 cm inlength along the longest length of the balloon, at most about 3.75 cm inlength along the longest length of the balloon, at most about 4 cm inlength along the longest length of the balloon, at most about 4.25 cm indiameter, at most about 4.5 cm in diameter, at most about 4.75 cm indiameter, at most about 5 cm in diameter, at most about 5.25 cm indiameter, at most about 5.5 cm in diameter, at most about 5.75 cm indiameter, at most about 6 cm in diameter, at most about 6.25 cm indiameter, at most about 6.5 cm in diameter, at most about 6.75 cm indiameter, at most about 7 cm in diameter, at most about 7.25 cm indiameter, at most about 7.5 cm in diameter, at most about 7.75 cm indiameter, at most about 8 cm in diameter, at most about 3 cm in lengthalong the longest length of the balloon, at most about 3.25 cm in lengthalong the longest length of the balloon, at most about 3.5 cm in lengthalong the longest length of the balloon, at most about 3.75 cm in lengthalong the longest length of the balloon, at most about 4 cm in lengthalong the longest length of the balloon, at most about 4.25 cm in lengthalong the longest length of the balloon, at most about 4.5 cm in lengthalong the longest length of the balloon, at most about 4.75 cm in lengthalong the longest length of the balloon, at most about 5 cm in lengthalong the longest length of the balloon, at most about 5.25 cm in lengthalong the longest length of the balloon, at most about 5.5 cm in lengthalong the longest length of the balloon, at most about 5.75 cm in lengthalong the longest length of the balloon, at most about 6 cm in lengthalong the longest length of the balloon, 6.25 cm in length along thelongest length of the balloon, at most about 6.5 cm in length along thelongest length of the balloon, at most about 6.75 cm in length along thelongest length of the balloon, at most about 7 cm in length along thelongest length of the balloon, at most about 7.25 cm in length along thelongest length of the balloon, at most about 7.5 cm in length along thelongest length of the balloon, at most about 7.75 cm in length along thelongest length of the balloon, and at most about 8 cm in length alongthe longest length of the balloon. As used herein with respect toballoon dimensions whether length or diameter, the term “about” meansvariations of at least one of 0.1 cm, 0.2 cm, 0.25 cm, 0.5 cm, and 1 cm.

Thus, provided herein is an implant configured to patch osteochondraldefects. The defects may occur due to injury, stress, naturallyoccurring, and/or may created or enhanced by a medical professionalduring a medical procedure. In some embodiments, the implant may becalled a patch having the balloon and an attachment element (orelements—which may be called appendages) described herein and may besized to fit within a defect in a manhole-cover type manner. In someembodiments, the implant may comprise balloon and attachment elementsdescribed elsewhere herein and may be configured to lay over a defect(full defect or partial defect). In some embodiments the implant asdescribed herein as used to patch or repair osteochondral defects may becalled a patch or a patch implant.

In some embodiments, the size of the balloon dimensions are prechosenbased on the individual patient need, and the balloon size (dimensions,geometry, length, depth, for non-limiting examples) is pre-set. In someembodiments, the balloon comprises multiple chambers which may beinflated (or deflated) selectively to fill the defect in situ or justprior to implantation in order to adjust the implant's balloon size(dimensions, length, width, depth, geometry, for non-limiting example)as needed at the time of implantation. The balloon (or any chamberthereof) of some embodiments can be secondarily inflated or deflated (orboth) in situ.

FIGS. 11A, 11B, and/or 110 may be used to describe a patch implantdescribed herein, having appendages 4 a, 4 c, extending from a balloon 6(not shown in FIG. 11A) and including holes 8 a-8 h, and/or tabs 10 a-10f which may be used with couplers (not shown) to couple the implant to abone of the knee joint (which may be the femur, the tibia, or thepatella). Features shown in FIGS. 11A, 11B, and/or 110 are common toboth the unicompartment knee implant (discussed elsewhere herein) andthe patch implant, although dimensions may differ as described herein.Thus, FIGS. 11A, 11B, and/or 11C may be used to describe theunicompartment knee implant and/or the patch implant. FIG. 11A depictsan embodiment of the patch implant 2 curved to simulate curvature aboutone condyle of a femur, the implant 2 having appendages 4 a, 4 c,extending from an uninflated balloon (not shown) and including tabs 10a-10 f and/or holes 8 a-8 h, which may be used with couplers (not shown,described elsewhere herein) to couple the implant 2 to the femur of theknee joint. FIG. 11B depicts an embodiment of the patch implant 2 curvedto simulate curvature about one condyle of a femur, the implant 2 havingappendages 4 a, 4 c, extending from an inflated balloon 6 and includingtabs 10 a-10 f and/or holes 8 a-8 h, which may be used with couplers(not shown, described elsewhere herein) to couple the implant 2 to thefemur of the knee joint. FIG. 11C depicts a bottom-up of gliding surfaceview of an embodiment of the patch implant 2 curved to simulatecurvature about one condyle of a femur, the implant 2 having appendages4 a, 4 c, extending from an inflated balloon 6 and including tabs 10a-10 f and/or holes 8 a-8 h, which may be used with couplers (not shown,described elsewhere herein) to couple the implant 2 to the femur of theknee joint. In some embodiments, the implant is configured to couple toa tibia. In some embodiments, the implant is configured to couple to atrochlear groove of a femur. In some embodiments, the implant isconfigured to couple to only a portion of a condyle of a femur.

FIGS. 12A, 12B, and/or 12C may be used to describe a patch implantdescribed herein, having appendages 4 a, 4 c, extending from a balloon 6and including holes 8 a, 8 b, 8 c, and/or tabs 10 a, 10 b. 10 c, 10 d,10 e, 10 f which may be used with couplers (not shown) to couple theimplant to a bone of the knee joint (which may be the femur, the tibia,or the patella). Features shown in FIGS. 12A, 12B, and/or 12C are commonto both the unicompartment knee implant (discussed elsewhere herein) andthe patch implant, although dimensions may differ as described herein.Thus, FIGS. 12A, 12B, and/or 12C may be used to describe theunicompartment knee implant and/or the patch implant. FIG. 12A depicts abottom-up view of an embodiment of the implant 2 (unicompartment orpatch), the implant having appendages 4 a, 4 c, extending from a balloon6 and including holes 8 a, 8 b, 8 c, which may be used with couplers(not shown) to couple the implant 2 to the femur of the knee joint. FIG.12B depicts a bottom-up view of an embodiment of the implant 2(unicompartment or patch), the implant having appendages 4 a, 4 c,extending from a balloon 6 and including tabs 10 a, 10 b and hole 8 awhich may be used with couplers (not shown) to couple the implant to thefemur of the knee joint. FIG. 12C depicts a bottom-up view of anembodiment of the implant 2 (unicompartment or patch), the implanthaving appendages 4 a, 4 c, extending from a balloon 6 and includingtabs 10 c, 10 d, 10 e, and 10 f and hole 8 a which may be used withcouplers (not shown) to couple the implant to the femur of the kneejoint. In some embodiments, the implant is configured to couple to atibia. In some embodiments, the implant is configured to couple to atrochlear groove of a femur. In some embodiments, the implant isconfigured to couple to only a portion of a condyle of a femur. In someembodiments the implant is coupled to the patella. In any embodiment theballoon 6 may extend from one surface of the implant as a focalprotuberance to fill a defect, space, or to aide in alignment correct,or the balloon may be full thickness as differences in FIGS. 2 and 3show respectively. In any embodiment there may be a singular or multiplemajor balloons, if off a primary surface resembling bubble wrap, andthere may be microscopic balloons or vacuoles containing gas, gel, orsolid in the material matrix.

In all descriptions provided herein of the patch implant, the implantmay instead be configured to couple to the tibia or to the fibula or thepatella. It is the intention and understanding that the implant issuited for this purpose in certain embodiments with adjustments toaccount for dimensional differences of these bones. Most descriptionsprovided herein are directed to embodiments coupling the implant to thefemur, however, this is primarily for ease of description andcontinuity, and does not preclude embodiments wherein the implant iscoupled to the tibia (or other bones). Likewise, as noted elsewhereherein, there are embodiments where the implant may be coupled to twobones (at least), for example to both a tibia and a femur.

Partial Knee Arthroplasty (Unicompartment)

In addition to the total knee-type (dual condyle) and patch implants areimplants that serve to cover and adjust alignment for either the medialor lateral condyle of the femur with varus or valgus knees requiringadded cushioning to recreate the natural six degrees of knee valgus.

Thus, provided herein is an implant for placement on at least onecondyle of the distal femur (a unicompartment implant—named so due totheir coverage of a single condyle of the femur). The implant may beconfigured to be placed over the lateral condyle. The implant may beconfigured to be placed over the medial condyle. The implant may beconfigured to be placed over either the medial condyle or the lateralcondyle. Two unicompartment implants may be placed in the same knee, oneover the medial condyle, one over the lateral condyle.

FIGS. 11A-12C depict example embodiments of unicompartment implants. Insome embodiments, the unicompartment implant comprises a balloon that isat least one of: at most about 1.5 cm in diameter, at most about 1.75 cmin diameter, at most about 2 cm in diameter, at most about 2.25 cm indiameter, at most about 2.5 cm in diameter, at most about 2.75 cm indiameter, at most about 3 cm in diameter, at most about 3.25 cm indiameter, at most about 3.5 cm in diameter, at most about 3.75 cm indiameter, at most about 4 cm in diameter, at most about 4.25 cm indiameter, at most about 4.5 cm in diameter, at most about 4.75 cm indiameter, at most about 5 cm in diameter, at most about 5.25 cm indiameter, at most about 5.5 cm in diameter, at most about 5.75 cm indiameter, at most about 6 cm in diameter, at most about 6.25 cm indiameter, at most about 6.5 cm in diameter, at most about 6.75 cm indiameter, at most about 7 cm in diameter, at most about 7.25 cm indiameter, at most about 7.5 cm in diameter, at most about 7.75 cm indiameter, at most about 8 cm in diameter, at most about 3 cm in lengthalong the longest length of the balloon, at most about 3.25 cm in lengthalong the longest length of the balloon, at most about 3.5 cm in lengthalong the longest length of the balloon, at most about 3.75 cm in lengthalong the longest length of the balloon, at most about 4 cm in lengthalong the longest length of the balloon, at most about 4.25 cm in lengthalong the longest length of the balloon, at most about 4.5 cm in lengthalong the longest length of the balloon, at most about 4.75 cm in lengthalong the longest length of the balloon, at most about 5 cm in lengthalong the longest length of the balloon, at most about 5.25 cm in lengthalong the longest length of the balloon, at most about 5.5 cm in lengthalong the longest length of the balloon, at most about 5.75 cm in lengthalong the longest length of the balloon, at most about 6 cm in lengthalong the longest length of the balloon, 6.25 cm in length along thelongest length of the balloon, at most about 6.5 cm in length along thelongest length of the balloon, at most about 6.75 cm in length along thelongest length of the balloon, at most about 7 cm in length along thelongest length of the balloon, at most about 7.25 cm in length along thelongest length of the balloon, at most about 7.5 cm in length along thelongest length of the balloon, at most about 7.75 cm in length along thelongest length of the balloon, and at most about 8 cm in length alongthe longest length of the balloon. As used herein with respect toballoon dimensions whether length or diameter, the term “about” meansvariations of at least one of 0.1 cm, 0.2 cm, 0.25 cm, 0.5 cm, and 1 cm.

In some embodiments, the implant comprises attachment tabs or attachmentelements over the anterior and/or posterior and/or medial side, and/orlateral side (and/or some combination thereof) of a condyle. In someembodiments, the implant comprises attachment tabs or attachmentelements in the intercondylar notch. In some embodiments, the implantcomprises attachment tabs or attachment elements superiorly at thedistal end of the femur anteriorly.

The posterior of the knee can be difficult to access without disturbingjoint components (or in order to minimize such disturbance) such astendons, ligaments, etc. Thus, in some embodiments, the implantcomprises strings, reigns, lassos, and/or lanyards that may pass fromthe posterior of the implant via the intercondylar notch anteriorly tojoin with themselves and/or other coupling devices. In some embodiments,posterior reigns or suture-like lanyards cinch up the implant frominside the posterior intercondylar notch toward another connection sitearound the femur. These couplers may be pre-coupled to the implant, andthe implant and its couplers may be configured to be pulled (or cinched)from the anterior of the implant once the implant is in its generallocation relative to the condyle in order to finally position theimplant about the condyle—in particular in order to cinch the implantabout the posterior of the condyle. Likewise, in some embodiments wherethe implant is pre-molded, the coupler as described are adapted to movethe implant to its final position with conformity to the condyle'sposterior with minimal disturbance to the joint structures at thejoint's posterior (minimal cutting, minimal moving, and or minimaldetachment, for non-limiting example). In some embodiments at least aportion of the ligamentary structure of the knee is spared.

FIG. 10A depicts a side view of an embodiment of the knee implant 20curved about at least one condyle 22 of a femur 24, the implant 20having appendages 4 b, 4 d extending from an inflated balloon 6 andshowing the inflation medium 46 moved anteriorly toward the patella 40when the knee joint is slightly flexed. Likewise, FIG. 10B depicts aside view of an embodiment of the knee implant 20 curved about at leastone condyle 22 of a femur 24, the implant 20 having appendages 4 b, 4 dextending from an inflated balloon 6 and having couplers 44 a, 44 b(which may be, for non-limiting example, staples or screws) coupling theappendages 4 b, 4 d to the femur 24 and showing the inflation medium 46moved anteriorly toward the patella 40 when the knee joint is slightlyflexed.

FIGS. 11A, 11B, and/or 110 may be used to describe a unicompartmentimplant 2 (or unicompartment knee implant, terms which may be usedinterchangeably) described herein, having appendages 4 a, 4 c, extendingfrom a balloon 6 (not shown in FIG. 11A) and including holes 8 a-8 h,and/or tabs 10 a-10 f which may be used with couplers (not shown) tocouple the implant to a bone of the knee joint (which may be the femur,the tibia, or the patella). Features shown in FIGS. 11A, 11B, and/or 110are common to both the unicompartment knee implant and the patch implant(discussed elsewhere herein), although dimensions may differ asdescribed herein. Thus, FIGS. 11A, 11B, and/or 11C may be used todescribe the unicompartment knee implant and/or the patch implant. FIG.11A depicts an embodiment of the unicompartment knee implant 2 curved tosimulate curvature about one condyle of a femur, the implant 2 havingappendages 4 a, 4 c, extending from an uninflated balloon (not shown)and including tabs 10 a-10 f and/or holes 8 a-8 h, which may be usedwith couplers (not shown, described elsewhere herein) to couple theimplant 2 to the femur of the knee joint. FIG. 11B depicts an embodimentof the unicompartment knee implant 2 curved to simulate curvature aboutone condyle of a femur, the implant having appendages 4 a, 4 c,extending from an inflated balloon 6 and including tabs 10 a-10 f and/orholes 8 a-8 h, which may be used with couplers (not shown, describedelsewhere herein) to couple the implant 2 to the femur of the kneejoint. FIG. 11C depicts a bottom-up view of an embodiment of theunicompartment knee implant 2 curved to simulate curvature about onecondyle of a femur, the implant 2 having appendages 4 a, 4 c, extendingfrom an inflated balloon 6 and including tabs 10 a-10 f and/or holes 8a-8 h, which may be used with couplers (not shown, described elsewhereherein) to couple the implant 2 to the femur of the knee joint.

In some embodiments, the unicompartment implant including attachmenttabs is at least one of: at most about 15 cm in length along the longestlength of the implant, at most about 15.25 cm in length along thelongest length of the implant, at most about 15.5 cm in length along thelongest length of the implant, at most about 15.75 cm in length alongthe longest length of the implant, at most about 16 cm in length alongthe longest length of the implant, at most about 16.25 cm in lengthalong the longest length of the implant, at most about 16.5 cm in lengthalong the longest length of the implant, at most about 16.75 cm inlength along the longest length of the implant, at most about 17 cm inlength along the longest length of the implant, at most about 17.25 cmin length along the longest length of the implant, at most about 17.5 cmin length along the longest length of the implant, at most about 17.75cm in length along the longest length of the implant, at most about 18cm in length along the longest length of the implant, 18.25 cm in lengthalong the longest length of the implant, at most about 18.5 cm in lengthalong the longest length of the implant, at most about 18.75 cm inlength along the longest length of the implant, at most about 19 cm inlength along the longest length of the implant, at most about 19.25 cmin length along the longest length of the implant, at most about 19.5 cmin length along the longest length of the implant, at most about 19.75cm in length along the longest length of the implant, at most about 20cm in length along the longest length of the implant, at most about20.25 cm in length along the longest length of the implant, at mostabout 20.5 cm in length along the longest length of the implant, at mostabout 20.75 cm in length along the longest length of the implant, atmost about 21 cm in length along the longest length of the implant, atmost about 21.25 cm in length along the longest length of the implant,at most about 21.5 cm in length along the longest length of the implant,at most about 21.75 cm in length along the longest length of theimplant, at most about 22 cm in length along the longest length of theimplant, at most about 22.25 cm in length along the longest length ofthe implant, at most about 22.5 cm in length along the longest length ofthe implant, at most about 22.75 cm in length along the longest lengthof the implant, at most about 23 cm in length along the longest lengthof the implant, 23.25 cm in length along the longest length of theimplant, at most about 23.5 cm in length along the longest length of theimplant, at most about 23.75 cm in length along the longest length ofthe implant, at most about 24 cm in length along the longest length ofthe implant, at most about 24.25 cm in length along the longest lengthof the implant, at most about 24.5 cm in length along the longest lengthof the implant, at most about 24.75 cm in length along the longestlength of the implant, at most about 25 cm in length along the longestlength of the implant, at most about 25.25 cm in length along thelongest length of the implant, at most about 25.5 cm in length along thelongest length of the implant, at most about 25.75 cm in length alongthe longest length of the implant, and at most about 26 cm in lengthalong the longest length of the implant. As used herein with respect toimplant length dimensions, the term “about” means variations of at leastone of 0.1 cm, 0.2 cm, 0.25 cm, 0.5 cm, and 1 cm.

In some embodiments, the unicompartment implant is longer than it iswide, and the longer portion of the implant wraps from the anterior ofthe condyle to the posterior of the condyle. In some embodiments, thelength of the implant is longer on the outer edge of the implant than onthe inner edge nearest the trochlear groove (whether used on the lateralor medial condyle).

FIGS. 12A, 12B, and/or 12C may be used to describe a unicompartment kneeimplant (unicompartment implant) described herein, having appendages 4a, 4 c, extending from a balloon 6 and including holes 8 a, 8 b, 8 c,and/or tabs 10 a, 10 b. 10 c, 10 d, 10 e, 10 f which may be used withcouplers (not shown) to couple the implant to a bone of the knee joint(which may be the femur, the tibia, or the patella). Features shown inFIGS. 12A, 12B, and/or 12C are common to both the unicompartment kneeimplant and the patch implant (discussed elsewhere herein), althoughdimensions may differ as described herein. Thus, FIGS. 12A, 12B, and/or12C may be used to describe the unicompartment knee implant and/or thepatch implant. FIG. 12A depicts a bottom-up view of an embodiment of theimplant 2 (unicompartment or patch), the implant having appendages 4 a,4 c, extending from a balloon 6 and including holes 8 a, 8 b, 8 c, whichmay be used with couplers (not shown) to couple the implant 2 to thefemur of the knee joint. FIG. 12B depicts a bottom-up view of anembodiment of the implant 2 (unicompartment or patch), the implanthaving appendages 4 a, 4 c, extending from a balloon 6 and includingtabs 10 a, 10 b and hole 8 a which may be used with couplers (not shown)to couple the implant to the femur of the knee joint. FIG. 12C depicts abottom-up view of an embodiment of the implant 2 (unicompartment orpatch), the implant having appendages 4 a, 4 c, extending from a balloon6 and including tabs 10 c, 10 d, 10 e, and 10 f and hole 8 a which maybe used with couplers (not shown) to couple the implant to the femur ofthe knee joint.

In all descriptions provided herein of the unicompartment implant, theimplant may instead be configured to couple to the tibia or to thefibula or the patella. It is the intention and understanding that theimplant is suited for this purpose in certain embodiments withadjustments to account for dimensional differences of the particularbones. Most descriptions provided herein are directed to embodimentscoupling the implant to the femur, however, this is primarily for easeof description and continuity, and does not preclude embodiments whereinthe implant is coupled to the tibia (or other bones). Likewise, as notedelsewhere herein, there are embodiments where the implant may be coupledto two bones (at least), for example to both a tibia and a femur.

Meniscal Replacement or Repair, and Solid, Rigid, or Semi-RigidComponents:

Provided herein is an implant having a balloon having a first and secondchamber. The implant may be any of the Dual Compartment, Unicompartment,and Patch implants described herein. The second chamber may beconfigured to replace and/or partially replace fibrocartilage meniscalloss. The implant may have two lobes of chambers which may bealternatively described as two superimposed balloon radii in appositionto each other. The implant may be configured to provide stabilitybetween the femur and tibia by providing a meniscus wedge. In someembodiments the implant comprises a portion configured to replace and/orpartially replace fibrocartilage meniscal loss. Such an embodiment maynot require a second chamber.

In some embodiments a chamber of the implant is configured to receive asolid piece configured to restore joint and/or bone alignment. In someembodiments, the chamber is configured to receive a plurality of solidpieces, each of which can be used to increase the space between a firstbone and a second bone in order to restore and/or improve joint and/orbone alignment. The solid pieces may be wedge-shaped, or be provided invarious sizes and/or shapes. The solid pieces may individually ortogether be used in a chamber or multiple chambers of the implant. Thesolid piece (or pieces) may be used to ratchet adjacent bones to adesired distraction and/or alignment to restore and/or improve jointand/or bone alignment. The solid piece may be put in a chamber of theimplant, which may enclose or partially enclose the piece to hold thepiece in place. In some embodiments, a block of biocompatible material(such as PMMA or another bone-like substitute) may be provided and maybe formed (by carving or other forming method) by the surgeon to adesired shape. The formed piece may then be put in a chamber of theimplant, which may enclose or partially enclose the piece to hold thepiece in place.

In some embodiments, the inflation medium is a methyl methacrylate orother biocompatible hardening substance which can flow when initiallyput into the chamber, and hardens to become a rigid piece (or solidpiece). The methyl methacrylate or other biocompatible hardeningsubstance may conform to the shape of the chamber, or may conform to theshape of a space between bones and/or other joint structures. The methylmethacrylate or other biocompatible hardening substance may conform to aform chosen by the surgeon using tools and/or pressure to influence thefinal shape of the rigid piece formed by the methyl methacrylate orother biocompatible hardening substance upon hardening.

In a separate embodiment, methylmethacrylate can be used on the boneengaging surface of the implant to secure the implant to the bone and/orcartilage. In another embodiment, the methylmethacrylate may be used tofill in space in the joint either between the bone or cartilage and theimplant or between the implant and the joint.

The solid piece (whether formed in situ or by a surgeon or pre-formed)may be cushioned by the implant. The implant may comprise an inflatablechamber between the solid piece and the femur. The implant may comprisean inflatable chamber between the solid piece and the tibia. The implantmay comprise an inflatable chamber between the solid piece and thepatella. The implant may comprise an inflatable chamber between thesolid piece and the second bone. The implant may comprise a pad betweenthe solid piece and the femur as a cushion. The implant may comprise apad between the solid piece and the tibia as a cushion. The implant maycomprise a pad between the solid piece and the patella as a cushion.

The solid piece may provide at least one of about 1 degree of jointcorrection, about 2 degrees of joint correction, about 3 degrees ofjoint correction, about 4 degrees of joint correction, about 5 degreesof joint correction, about 6 degrees of joint correction, about 7degrees of joint correction, about 8 degrees of joint correction, about9 degrees of joint correction, and about 10 degrees of joint correction.With respect to degrees of joint correction, the term “about” can meanranges of 1%, 5%, 10%, 25%, or 50%.

The implant can be used in a variety of joints where the implantreplaces a bone on bone surface and cushions the interaction between thearticular ends of any two bones, such as at the femoral tibial andpatella femoral knee interfaces. Where the implant is substituting orenhancing articular cartilage, the rigidity can be reduced or enhancedto maximize conformation changes that arise during motion as enabled bythe two opposing walls and intended inner space, coupled withconsiderations in any joint surgical reconstruction with accommodationto or amplification of the existing joint ligaments, tendons or dearththereof. The implant 10 may be deflated and removed by minimallyinvasive surgery, for example, after the implant has served its purposeof regenerating tissue or if another clinical condition warrants itsremoval. However, it may not be clinically necessary to remove theimplant even if inflation is lost, since the two remaining functions ofpatching the injured cartilage, and delivering restorative cells mayjustify implant retention.

In many embodiments the implant (or a portion thereof, such as theballoon or balloon) is a weight bearing spacer that will allow jointmotions to approach normal, whether filling the space left by anentirely collapsed peripheral joint bone or the space of ablatedcartilage proximate surfaces diffusely as in osteoarthritis orsuccinctly as in osteonecrotic defects or localized trauma. The wallsmay be used as a membrane for holding living cells in proximity of theosteochondral defect long enough for the cells to attach (e.g. 24 hours)or to deeply adhere (up to 28 days) or return to normal (up to oneyear). Weight bearing will be expected to increase as distal lowerextremity joints are treated.

Kits

Provided herein are kits comprising multiple implants described herein.A kit may comprise multiple sizes of a single type of implant. A kit maycomprise various implant types, such as the patch, the unicompartment,and/or the dual compartment types of implants described herein. A kitmay comprise various couplers, which may be selected by the surgeondepending on his comfort and expertise, and/or based on the particularpatient anatomy and/or needs. The kit may further comprise any insertiontools and/or surgery tools that may uniquely assist in implanting theimplant in the patient.

Implantation Methods

Implantation of implants provided herein will depend on the size ofjoint surface intended for reconstruction by use of the implant. In someembodiments, an arthroscope can be inserted in one side of the kneejoint through a 0.5 cm wound, while the implant is inserted into theopposite joint line wound from 1-10 cm in size. The joint may be firstinspected and debrided, performing an arthroscopic synovectomy,chondroplasty, and meniscectomy as needed. Additional distraction undergeneral anesthesia with the knee at variable degrees of flex may allowfor implant introduction, systematic peripheral attachment, balancing,and inflation.

In some embodiments, the implant may be selectively inflatable dependingon the particular needs of the patient. In some embodiments, the fillerof the interior of the implant may be rigid, semi-rigid, fluid, air, orcombinations thereof, as described herein. In some embodiments, theimplant may be used in conjunction with fibrocartilage repair orreplacement. In some embodiments, the implant may be used withoutfibrocartilage repair or replacement. In some embodiments, the implantmay be used in conjunction with boney osteotomy. In some embodiments,the implant may be used without boney osteotomy.

The posterior of the knee can be difficult to access without disturbingjoint components (or in order to minimize such disturbance) such astendons, ligaments, etc. Thus, in some embodiments, the method comprisesproviding an implant comprising strings, reigns, lassos, and/or lanyardsthat may pass from the posterior of the implant via the intercondylarnotch anteriorly to join with themselves and/or other coupling devices.In some embodiments, posterior reigns or suture-like lanyards cinch upthe implant from inside the posterior intercondylar notch toward anotherconnection site around the femur. In some embodiments, the methodscomprise conforming the implant posterior to the condyle by pulling thestrings (or reigns, or lassos, or lanyards or the like) of the implant.Such couplers (strings, reigns, lassos, lanyards, etc) may comprisesuture materials and/or wire materials.

These couplers (i.e. strings, reigns, lassos, lanyards, etc) may bepre-coupled to the implant, and the implant and its couplers may beconfigured to be pulled (or cinched) from the anterior of the implantonce the implant is in its general location relative to the condyle inorder to finally position the implant about the condyle—in particular inorder to cinch the implant about the posterior of the condyle. Likewise,in some embodiments where the implant is pre-molded, the coupler asdescribed are adapted to move the implant to its final position withconformity to the condyle's posterior with minimal disturbance to thejoint structures at the joint's posterior (minimal cutting, minimalmoving, and or minimal detachment, for non-limiting example). In someembodiments at least a portion of the ligamentary structure of the kneeis spared.

The implant is inserted arthroscopically through a cannula about 10 mmin diameter with the implant in the deflated construct, and once insidethe prepared joint space and secured therein by the skirt or tabs, theimplant will be distended or inflated with gas, gel, fluid or fluid thatbecomes a resilient solid to fill the original natural space of about0.5 cm between the bones of the joint (between at least two bones of thejoint). If the implant is not inserted through a cannula, it may beinserted through an open incision from one to forty centimeters inlength at the surgeons discretion. Tensioning will be by the surgeon'ssense of proper pressure application aided by a gauged syringe forinsertion of viscolubricants such as Synvisc, Hyalgan, Supartz and/oranalgesics such as lidocaine gel. The insertion of liquids to the jointper se may be directly, through a cannula to the joint space previouslyin place for debridement, and or via a cannula or tube that is not partof the original implant assembly. Once the joint is cleaned, the implantis inserted and appropriately fixed to avoid extrusion or dislocationthereof. This may be via attachment of the implant tabs and/or by acombination of tab use plus intended friction created by implant surfacecoverings (analogous to Velcro) or a draw string at the smaller base ofthe implant.

In some embodiments the attachment tabs are positioned on the implant toboth secure the implant to the joint components, and to enable aphysician to ensure the implant has a minimum amount of slack that couldcreate wrinkles or loose areas to avoid unnecessary friction and/or wearof the implant of the patient's anatomy. Figures depicted herein showexamples of properly situated attachment tabs configured for these dualpurposes. In some embodiments, fewer tabs are needed to achieve thesegoals.

In some embodiments, where slack or voids exist, the balloon undercompression may fill such areas. The implant in some embodiments isconfigured to allow hyaline and/or cartilage cells to fill anyirregularities or craters in the joint components and grow to refurbishnatural joint contour. When the implant implantation is combined with,for example, movement of the treated joint in a constant passive motionmachine for 12 hrs a day for 6 weeks after surgery implanting theimplant, cell growth will create renewed hyaline cartilage, and/orblood/fibrin and scar to create fibrocartilage filler material.

Each attachment tab insert site may be clinically determinedcentripitally around the implant during surgery, driving slots or holessequentially with an osteotome or drill immediately followed byinsertion of the triangled tab extension into the bone slots or screwrespectively. For example, if the implant were viewed like a clockfacethe first tab could be tacked/tapped in a 2 o'clock, then 7, 10, 4 11,5, 12, 6 (wherein #2, 7, 10, 4 are over the bilateral femurssuperior/inferior to collateral ligaments, 11, 12 are superior at thedistal anterior femur beneath the upper patella, and 5, 6 are inside theintercondylar notch anterior to cruciates.) This can be like putting asaddle on a horse, going around the knee end with a grasper, to tug thepolymer toward fit, tapping a slot over the side of the femur with athin one-half inch osteotome, angling cuts distally, one by one, as ifto pull the implant (or saddle) into its angle of repose, seatingideally over the condyles and ridings nicely in the trochlear groove.

In some embodiments, the metal clips could be set angled at about 120degrees, as greater than 90 will favorably distract/hold the implant totighter fit analogous to a mylar compliant balloon or stretch sockfitting over a protuberance as opposed to a piece of (non-compliant)paper that results is wrinkles and areas of incongruence between theimplant and bone end. Reducing dislodgement tendency and snugging thepolymer once stretched to best fit may avoid the failure history asillustrated in the Danish Polymer hip cap solid crescent shaped hipresurfacing implants which lacked inflation, surface stability,accommodation, and fixation.

Inflation may also be specified by clinical need, and modifications inthe implant multi-cell (multi-compartment) construction allows forselective inflation with substances ranging from gas to solid, includinggels or semi-solids that can as part of material layered integrityeither provide calculated hardness (durometer) to overcome and resistlimb adjacent bone mal-alignment, and/or to deliver new regenerativetissues for restoration of natural anatomy of time. That is, certainsections of the implant may be electively inflated of left withoutexpansion, to adjust to fit as matching a normal or uninjuredcontralateral limb for the involved patient.

Indeed, patient interaction and feedback may be sought so as to bring toorthopedic conceived art and science the individual's own needs andconcerns. It is said that for patients who have anterior cruciateinjuries, one third require reconstruction for knee joint stabilizer,one third do not—living with a reduced activity level, and one thirddeliberate extensively until a choice between the two continuum optionsis made.

A goal of embodiments of implants described herein is to maintainremnant living tissue by using minimally invasive technologies, smallerincisions when they serve the patient equally to larger, sacrificing theleast normal tissue as possible. Implants described herein assist andimprove on current treatment options available by avoiding as much aspossible the ablative bone and cartilage resecting, ligament removingtotal knee arthroplasty and instead to restore the padding lost ininjury or disease or surgery.

Examples from within the techniques include electing to repair ratherthan reconstruct anterior cruciate ligaments in certain situations,proved warranted and effective at a p<0.3 statistical level. WhereasCarticel chondrocyte implantation is useful to enable articular surfaceregrowth with hyaline, rather than scar/fibrocartilage frompicking/drilling, the massive morbidity from periosteal harvesting isunnecessary. This is because it takes only 24 hours for the cartilagecloned chondrocytes to attach to the prepared joint surface, and thepolymer membrane (patch implant described herein, for example, or use ofchondrocytes on surfaces of the dual compartment implant or theunicompartment implant) over the prepared defect (like a manhole cover)will adeptly substitute for periosteum.

With these concepts in mind in is the overall intent to do what isnecessary to restore function and nothing more in order to spare thepatient removal of injured tissues that may recover or regrow, byimplementing a common sense approach to limb repair and reconstructionwith the implant and methods of use thereof. In animals as horses anddogs, where recovery instructions are even less likely to be followedthan with humans, implanting secure restorative implants for jointsurface refurbishment may offer renewed function and save lives thatwould have otherwise been sacrificed.

Rehabilitation of knee implant treated patients will engage prudentearly motion. The amount of weight bearing allowed with be analogous tothe procedures written by this primary surgery for Carticel implantedcases, following the principles that excessive amounts and repetitionsof stress upon reconstructed areas should be avoided for 6-12 weeksafter surgery. However, the knee implant surgeries per se are expectedto take less than one hour, involve less than 1 cc blood loss, requirewounds less than or equal to 10 cm overall (depending on the embodimentof the implant), and the end result intends to permit early full weightbearing. Zealous sports activities may be restricted until the boneingrowth and cartilage renewal is reasonably expected, between 2 and 12months after surgery depending upon the amount of joint tissue replaced.

In some situations, the removal of the implant may be needed, andembodiments of the implants described herein are configured for removalarthroscopically, and with the allowance to perform all regular olderroutine accepted techniques ranging from joint debridement to drilling,partial or total replacement. In some embodiments the implant isconfigured for removal and replacement with a replacement implant—eitherimmediately (within a week), or after a period of longer time (forexample, after about 6 weeks to 1 year in the case of infection once allforeign bodies are removed and depending upon the surgeon's and/orinfectious disease consultant's opinion.

Specific surgical decisions related to size matching, fixation and orconcomitant osteotomy warranted reconstruction are left to the primarysurgeon and patient in each case.

The implant is inserted by minimally invasive surgery, in someembodiments, however, in other embodiments, the implant may not beinserted by minimally invasive surgery. In some embodiments, the implantis delivered through an incision that is about 0.5 inches long. In someembodiments, the implant is delivered through an incision that is about1 centimeter long. In some embodiments, the implant is delivered throughan incision that is at most about 1 inch long. In some embodiments, theimplant is delivered non-arthroscopically through an incision that is atleast 1 centimeter long. In some embodiments, the implant is deliveredthrough an incision that is at most about 0.75 inches long. In someembodiments, the implant is delivered through an incision that is atmost about 0.5 inches long. In some embodiments, the implant isdelivered through an incision that is about 8 centimeters long. In someembodiments, the implant is delivered through an incision that is about9 centimeters long. In some embodiments, the implant is deliveredthrough an incision that is about 10 centimeters long. In someembodiments, the implant is delivered through an incision that is about11 centimeters long. In some embodiments, the implant is deliveredthrough an incision that is about 12 centimeters long. In someembodiments, the implant is delivered through an incision that is overabout 10 centimeters long. In some embodiments, the implant is deliveredthrough an incision that is at up to about 40 centimeters long. In someembodiments, the implant is delivered through multiple incisions. Withrespect to incision length, the term “about” can mean ranges of 1%, 5%,10%, 25%, or 50%.

In some embodiments the implant is configured to be delivered to thejoint arthroscopically. In some embodiments, the implant is configuredto fit within a cannula having a distal end inner diameter of at most 10millimeters. In some embodiments, the implant is configured to fitwithin a cannula having a distal end inner diameter of at most 9millimeters. In some embodiments, the implant is configured to fitwithin a cannula having a distal end inner diameter of at most 5millimeters.

In some embodiments, the implant is configured to fold in order to fitwithin a cannula having a distal end inner diameter of at most 10millimeters. In some embodiments, the implant is configured to fold inorder to fit within a cannula having a distal end inner diameter of atmost 9 millimeters. In some embodiments, the implant is configured tofold in order to fit within a cannula having a distal end inner diameterof at most 5 millimeters.

In some embodiments, the implant is configured to be delivered to ajoint through a cannula having a distal end inner diameter of at most 10millimeters. In some embodiments, the implant is configured to bedelivered to a joint through a cannula having a distal end innerdiameter of at most 9 millimeters. In some embodiments, the implant isconfigured to be delivered to a joint through a cannula having a distalend inner diameter of at most 5 millimeters.

In some embodiments the implant is configured to be delivered to thejoint arthroscopically. In some embodiments, the implant is configuredto fit within a cannula having a distal end inner diameter of at mostabout 10 millimeters. In some embodiments, the implant is configured tofit within a cannula having a distal end inner diameter of at most about9 millimeters. In some embodiments, the implant is configured to fitwithin a cannula having a distal end inner diameter of at most about 5millimeters. With respect to cannula distal end inner diameter, the term“about” can mean ranges of 1%, 5%, 10%, 25%, or 50%.

In some embodiments, the implant is configured to fold in order to fitwithin a cannula having a distal end inner diameter of at most about 10millimeters. In some embodiments, the implant is configured to fold inorder to fit within a cannula having a distal end inner diameter of atmost about 9 millimeters. In some embodiments, the implant is configuredto fold in order to fit within a cannula having a distal end innerdiameter of at most about 5 millimeters. With respect to cannula distalend inner diameter, the term “about” can mean ranges of 1%, 5%, 10%,25%, or 50%.

In some embodiments, the implant is configured to be delivered to ajoint through a cannula having a distal end inner diameter of at mostabout 10 millimeters. In some embodiments, the implant is configured tobe delivered to a joint through a cannula having a distal end innerdiameter of at most about 9 millimeters. In some embodiments, theimplant is configured to be delivered to a joint through a cannulahaving a distal end inner diameter of at most about 5 millimeters. Withrespect to cannula distal end inner diameter, the term “about” can meanranges of 1%, 5%, 10%, 25%, or 50%.

In some embodiments the implant may be provided as a deflated balloonfor insertion into the joint space. In some embodiments the implant maybe provided as folded balloon that may be collapsed like an umbrella forinsertion into the joint space. In some embodiments the implant may beprovided as collapsed balloon that is of an irregular folded pattern tominimize its folded (or collapsed) size for insertion into the jointspace. In some embodiments, the implant is configured to blow up (orexpand) to take the form of the expanded, distracted, debrided joint.

In some embodiments, the implant replaces periosteum.

In some embodiments, the implant is implanted to preserve bone ascompared to a typical arthroplasty procedure of the joint. In someembodiments, the implant is implanted to preserve cartilage as comparedto a typical arthroplasty procedure of the joint. In some embodiments,the implant is implanted with minimal soft tissue dissection as comparedto a typical arthroplasty procedure of the joint. In some embodiments,the implant is implanted without joint dislocation. In some embodiments,once implanted, the joint is adaptable to revision surgery. In someembodiments once implanted, the joint retains at least one of: about 90%of normal joint function, about 95% of normal joint function, about 85%of normal joint function, about 80% of normal joint function, about 75%of normal joint function, about 70% of normal joint function, about 65%of normal joint function, about 60% of normal joint function, about 55%of normal joint function, about 50% of normal joint function, at least95% of normal joint function, at least 90% of normal joint function, atleast 85% of normal joint function, at least 80% of normal jointfunction, at least 75% of normal joint function, at least 70% of normaljoint function, at least 65% of normal joint function, at least 60% ofnormal joint function, at least 55% of normal joint functions at least50% of normal joint function, about 50%-about 75% of normal jointfunction, about 50%-about 70% of normal joint function, about 60-about70% of normal joint function, about 70%-about 80% of normal jointfunction, about 70%-about 90% of normal joint function, about 80%-about95% of normal joint function, about 80%-about 90% of normal jointfunction, and about 90%-about 95% of normal joint function. As usedherein with respect to percentage of normal joint function, the term“about” can be ranges of 1%, 5%, 10%, or 25%. For example, a range of 1%with respect to about 90% of normal joint function covers 89% to 90% ofnormal joint function.

In some embodiments, prior to deploying the implant embodying featuresof the invention, the cartilage lining the joint is prepared by removinghyaline or fibro cartilage flaps or tears, and areas of chondraladvanced fissuring are excised or debrided to create precisely defineddefects surrounded by stable normal remnant hyaline cartilage withvertical edges in relation to the damaged surface. It is these defectsof the cartilage previously normal surface into which new living cellsmay be injected or otherwise inserted, and allowed to aggregate by theimplant interpositional arthroplasty proximate expanded compressiveexternal wall material. Synovitis invading the joint periphery may bevaporized and extracted conventionally or by the use of steam. Areas ofgreater cartilage damage are removed for subsequent regeneration and theless afflicted areas having stable cracks are treated to seal or weldthe cracks. Areas where the tugor or consistency or minimally damagedcartilage can be preserved are intentionally saved rather than destroyedso as to support the normal spacing and gliding opportunity of the morenormal joint interface. Thus, normal cartilage is left behind andabnormal cartilage is removed with the implant making up for thedeficiencies. With the present invention, it is preferred in someembodiments to avoid joint dislocation so as to preserve naturalinnervations and vascularity and thus preserving the blood supply.

Joint preparation is usually performed under a brief general anestheticof outpatient surgery. Increasing the joint space may be necessary andallows the surgeon to wash out noxious enzymes, to remove invasivesynovitis, to remove loose bodies, to prepare osteochondral defectsideally and otherwise prepare the joint for the implant. Partial orcomplete inflation of the implant may precede release of traction insome embodiments. In some embodiments, regeneration agents or cells areinserted with the implant or as a fluid or 3-D template prior to releaseof traction and wound closure. It is preferred, in some embodiments, toperform joint debridement, implant deployment and application of cellregeneration agent, e.g. stem cell application, under the sameanesthetic. As described by several companies in the Stem Cell Summitheld in New York, N.Y. on Feb. 17, 2009, it is desirable to obtain anaspiration of the patient's bone marrow from the iliac crest afteranesthesial sterilely at the beginning of the operation. Theintraoperative technologist will “dial in the cells” to regenerate areasof maximum pathophysiology while the surgeon debrides or otherwiseprepares the joint and inserts the implant, placing the cells at thebest time. Cell implantation may also occur as a secondary or tertiaryreconstructive treatment adjunct.

Provided herein is a method for restoring a joint comprising: providingan implant configured for deployment between a femur and at least onesecond bone of a joint, the implant comprising a balloon comprising afirst portion that is configured to engage the femur of the joint, asecond portion that is configured to engage at least one second bone ofthe joint, a side portion connecting the first portion and the secondportion, in which the side portion facilitates relative motion betweenthe first portion and the second portion, and an interior that isoptionally inflatable with a first inflation medium; and coupling afirst appendage of the balloon to the femur of the joint. Providedherein is a method for restoring a joint comprising: providing animplant configured for deployment between a tibia and at least onesecond bone of a joint, the implant comprising a balloon comprising afirst portion that is configured to engage the tibia of the joint, asecond portion that is configured to engage at least one second bone ofthe joint, a side portion connecting the first portion and the secondportion, in which the side portion facilitates relative motion betweenthe first portion and the second portion, and an interior that isoptionally inflatable with a first inflation medium; and coupling afirst appendage of the balloon to the tibia of the joint.

In some embodiments, at least two of first portion, the second portion,and the side portion are contiguous. In some embodiments, the firstportion comprises a first wall, the second portion comprises a secondwall, and the side portion comprises a side wall.

In some embodiments the method comprises providing an ingrowth patch onat least one of the first portion configured to engage the femur, thesecond portion configured to engage the second bone, the side portion,and the appendage. In some embodiments the method comprises providing aningrowth patch on at least one of the first portion configured to engagethe tibia, the second portion configured to engage the second bone, theside portion, and the appendage. The ingrowth patch may be configured toencourage and/or promote tissue ingrowth, such as bone ingrowth, fornon-limiting example. The patch may be as large as the portion itself(whether the first portion the second portion, the side portion, or theappendage) or may be smaller than the portion (such as in the shape of astrip or other shaped patch). The ingrowth patch may comprise a surfaceirregularity or roughness. The ingrowth patch may be Velcro-like. Insome embodiments the implant comprises an ingrowth patch on the firstportion and/or the second portion, from (and in some embodimentsincluding) a first appendage to a second appendage. In some embodiments,wherein the appendages loosen from attachment from the bone (by designand/or from wear and/or over time), the ingrowth patch aids in securingthe implant to the bone. In some embodiments, the ingrowth patchcomprises beads and/or bead-like elements attached to the implant. Suchan ingrowth patch may be configured to simulate trabecular bone space ofa normally cancellous latticework. In some embodiments, the beads aresintered beads of various sizes. In some embodiments, the beads aresintered beads about 400 microns in size. With respect to bead size, theterm “about” can mean ranges of 1%, 5%, 10%, 25%, or 50%. In someembodiments, the first bone and/or the second bone is roughened toacquire a bleeding bone to facilitate ingrowth. In some embodiments,about 0.5 mm of cortical tissue is removed to facilitate ingrowth.

In some embodiments, the method comprises coupling a second appendage ofthe balloon to the femur of the joint. In some embodiments, the methodcomprises coupling a second appendage of the balloon to the tibia of thejoint. In some embodiments, the method comprises coupling a secondappendage of the balloon to at least one second bone of the joint. Insome embodiments, the method comprises coupling a second appendage of atleast one of the first portion, the second portion, and the side portionto at least one of the femur and at least one second bone of the joint.In some embodiments, the method comprises coupling a second appendage ofat least one of the first portion, the second portion, and the sideportion to at least one of the tibia and at least one second bone of thejoint. In some embodiments, coupling at least one of the first appendageand the second appendage provides ligamentary-like support to the femurand the at least one second bone of the joint. In some embodiments,coupling at least one of the first appendage and the second appendageprovides ligamentary-like support to the tibia and the at least onesecond bone of the joint. In some embodiments, coupling at least one ofthe first appendage and the second appendage provides ligamentary-likesupport to the joint. In some embodiments, the first appendage and thesecond appendage are configured to provide tendon-like support to thefemur and the at least one second bone of the joint. In someembodiments, the first appendage and the second appendage are configuredto provide tendon-like support to the tibia and the at least one secondbone of the joint. In some embodiments, the first appendage and thesecond appendage are configured to provide tendon-like support to thejoint.

In some embodiments, the method comprises providing an inflation port incommunication with the interior of the balloon for inflation of theinterior of the balloon with the first inflation medium. In someembodiments, the method comprises using an inflation port of the implantthat is in communication with the interior of the balloon to inflate theinterior of the balloon with the first inflation medium. In someembodiments, the method comprises puncturing the balloon to inflate theinterior of the balloon with the first inflation medium. In someembodiments, the method comprises providing a balloon havingself-sealing capability. In some embodiments, the method comprisesproviding a balloon having self-sealing capability upon inflation of theinterior of the balloon with the first inflation medium. In someembodiments, the method comprises providing a balloon comprising a sealcapable of closing the interior of the balloon.

In some embodiments, the method comprises providing a balloon having aninterior comprising a plurality of inflatable chambers. In someembodiments, the interior comprises a plurality of individuallyinflatable chambers. In some embodiments, the method comprises inflatinga first chamber of the plurality of inflatable chambers with a firstinflation medium. In some embodiments, the first chamber and theinflation medium is selected based on the particular needs of thepatient. For non-limiting example, if the patient has bone loss due toan injury, the chamber may be selected at the location of the missingbone, and may be filled with a rigid inflation medium (or one thatbecomes rigid once in the chamber) in order to replace the missingand/or damaged bone. Alternatively, or in addition, a chamber may bechosen to restore alignment of the joint, and inflated with anappropriate inflation medium to impart both alignment and cushion to thejoint. In some embodiments, the method comprises inflating a secondchamber of the plurality of individually inflatable chambers with asecond inflation medium.

In some embodiments, the balloon is a composite structure. In someembodiments, the balloon comprises layers of porous and/or non-porousmaterials, or otherwise contain treatment or cell regeneration agents.In some embodiments, a first layer of the balloon is a thin, but stronglayer of a thermoplastic, such as a thermoplastic polyurethane, fornon-limiting example, which has microporosity sufficient to allowpassage or egress of treatment or cell regeneration agents from a secondlayer. The second layer may be a central layer (which lies between thefirst layer and a third layer or a fourth layer or more layers). Thefirst layer may comprise a bone engaging surface in some embodiments.The degree of microporosity to enable egress of treatment or cellregeneration agents from the second layer is found in polymer layerssuch as Chronoflex or Bionate 55. The bone engaging surface of theimplant may be coated and/or impregnated with a latticework of polymerthat is surface sprayed or layered on the bone engaging surface of theimplant to promote cartilage tissue regeneration. This bone engagingsurface coating may contain living chondrocytes (for example, as isprovided in the Carticel procedure by the Genzyme company), and/or maycontain stem cells with directed gene mutations to enhance adherence ofthe coating to the implant. The bone engaging surface may comprise peaksand troughs. The living cells may be provided in troughs while thesurface peaks may be used for at least one of: space validation,traction, and cell protection. Either surface may be coated with othercoatings such as anti-infectives, lysophosphatidic acid, hyaluronicacid, hydrogels, or biophosphates.

In some embodiments, the first inflation medium imparts rigidity in theimplant. In some embodiments, the first inflation medium imparts cushionin the implant. In some embodiments, the inflation medium chosen for thefirst inflation medium, and/or the particular choice of chamber (inembodiments having multiple chambers) filled with such first inflationmedium aligns the joint. In some embodiments, the inflation mediumchosen for the first inflation medium, and/or the particular choice ofchamber (in embodiments having multiple chambers) filled with such firstinflation medium aligns the bones of the joint. In some embodiments, theinflation medium chosen for the first inflation medium, and/or theparticular choice of chamber (in embodiments having multiple chambers)filled with such first inflation medium changes the bone alignment. Insome embodiments, the inflation medium chosen for the first inflationmedium, and/or the particular choice of chamber (in embodiments havingmultiple chambers) filled with such first inflation medium improvesjoint alignment. In some embodiments, the inflation medium chosen forthe first inflation medium, and/or the particular choice of chamber (inembodiments having multiple chambers) filled with such first inflationmedium restores, at least in part, joint alignment. In some embodiments,individual chambers of the interior are selectively inflated with afirst inflation medium and/or a second inflation medium. In someembodiments, individual chambers of the interior are selectivelyinflated with a first inflation medium and/or a second inflation mediumin order to reconstruct the joint and/or in order to reconstruct bonesof the joint.

Over time, ingrowth of repair tissue aids in fixation and stabilityexternally to the implant, while the soft cushioning implant interiorwill absorb forces across the joint surfaces and permit proper motion.The turgor or wall tension of the implant as well as the insidedistension of the implant per se can be adjusted by adding or removingthe inflation substance to the implant's interior space.

Accordingly, the present invention provides a new approach toarthroplasty that involves a resilient implant deployed between bones ofthe knee joint. Whereas a joint is comprised of the interface betweenbone cartilage space cartilage bone, in certain joint spaces such as theknee, the invention cushion may expand to fit the spaces between both“knee joints”—the femoral tibial involved on standing or walking on alevel plane, and the patella femoral bones of the knee more involved onstair ascent and decent. For example, pressures behind the knee cap orpatella when lying are zero, when standing are 0.7 times body weight,and when going up and down the patella femoral pressures are 3-4 timesbody weight. Thus, the implants will need to accommodate all the normalbody functional pressures and complex space movements. The implantembodying features of the present invention provides more physiologicmotion and shock absorption within the joint and has combinedcharacteristics of anatomic design symmetry, balanced rigidity withsufficient attachment connections to adjacent normal structures, anddurability that meet the needs of joint reconstruction.

The opposing internal surfaces of the first and second walls of theinvention may either move together in synchrony or in oppositedirections from one another (e.g. the superior wall moving medially inthe hip and the inferior wall moving laterally). Optionally, the implantmay be fixed to a concave surface of the joint or to a convex surface ofthe joint, to both, or to neither (e.g., having an interference fitwithin the joint with an expanding balloon or cushion that fills theexisting space). The implant may be inserted arthroscopically like adeflated balloon and then inflated through a cannula into the jointstructure) to act as a cushion or renewed interface for painless andstable limb motion. When feasible joint capsular and adjacent ligamenttissue as well as bone will be left in place to preserve the naturalbody, unless interfering with reconstructed limb function.

The application of steam in addition to removing damaged debris, cansmooth out and reform the joint surface. The high temperature of thesteam tends to weld cracks or fissures which can be present in thecartilage surface of a damaged joint. Smoothing of joint surfacecartilage with steam welds or seals existing cracks or flaps in thecartilage, especially superficially as the lamina splendors, which melttogether to provide a white shiny gliding joint surface. In cases wherebone is exposed, the steam can be used to stabilize the periphery of thedefect in the joint surface via capsulorrhaphy or joint tightening. Openmechanical and chemical debridement may also be employed to prepare thesurfaces for the implant.

Once the implant is secured to the femur by means of the skirt or tabsor using other couplers, an impregnated transfer medium or cell templatemay be used, as described by Histogenics and Tygenix chondrocytesdelivery systems wherein the position of concentrated cells ismechanically placed about the implant at areas of greatest cartilagedamage to promote regrowth, or as in Carticel wherein watery cells areimplanted beneath a periosteal membrane (a wall of the implant servingas the membrane), prior to completion of the inflation or expansion ofthe implant. At syringe or gauged device with measured screw-homepressure is used to inflate the implant.

Once the joint is ready to receive the implant, the deflated implant isadvanced through the diaphragm of a delivery cannula (such as the Acufexfrom Smith & Nephew) or through the open incision site into the joint.It can be inflated by the attached cannula using a common syringe,inserting several cc's of filler material. Inserted contents andlocations of cell placements depend on areas of need and joint size. Insome embodiments of the methods several cc's of filler material and aviscolubricant in the interior of the implant will allow distension,cushioning, and gliding movements. Cell regeneration agents are placedin the areas of greatest need.

Methods of living stem cell or chondrocyte placement depend on thelesions and specific implant construct. Direct infusion into the jointwith completion of implant inflation will press the cells into thehyaline surface, whereupon they attach within the first 24 hours. As aresult, the patient may be forced to remain sedentary and the jointwhere the implant is deployed, non-weight bearing for the first dayafter surgery. Deeper osteochondral defects can be treated by‘hyper-perfusion of cells’ via either 3-D cell transfer templates, ormicroneedle injection as used in treatment of diabetic patients forblood sugar testing and insulin/transdermal drug delivery. In cases ofosteochondritis dissecans or localized both cartilage and bone lose,bone graft may be packed into the base of the defect followed byaddition cell/tissue application. The cannula attached to the implantmay be sealed and detached, or left in place for periodic aspiration ofnoxious enzymes as for the Cox-1, Cox-2, and 5-Lox systems, followed byreinsertion of activated substances including viscolubricants, or evenmore cells.

Implants embodying features of the invention may be designed forpermanent or temporary deployment within a joint structure. Moreover,the implant may be formed of suitable bioabsorbable materials so thatthe implant may be absorbed within a particular predetermined timeframe. Suitable bioabsorbable materials include polylactic acid,polyglycolic acid, polycaprolactone, copolymers, blends and variantsthereof. One present method of forming the implant is to apply numerouslayers of polymer such as ChronoFlex AR in a solvent and evaporating thesolvent after applying each layer.

The coupling aspects (couplers) including but not limited to skirting orfixation tabs of the present implant prevent joint migration during use.

In some embodiments, the implant is adapted to restore natural jointfunction. In some embodiments, the implant is adapted to preserve viablejoint tissue. In some embodiments, the implant is adapted to be placedwith minimal surgery as compared to joint replacement therapy currentlymarketed. In some embodiments, the implant is adapted to permit weightbearing post surgery within at least one of: about 1 week, within about1 day, within about 2 days, within about 3 days, within about 4 days,within about 5 days, within about 6 days, within about 10 days, withinabout 2 weeks, within about 3 weeks, within about 4 weeks, within about5 weeks, within about 6 weeks. In some embodiments, the implant isadapted to permit weight bearing post surgery after about 1 day whereinfull weight bearing is allowed in about 6 weeks. As used herein withrespect to weight bearing timing, the term “about” can be a range of 1day, 2 days, or 3 days, in some embodiments. In some embodiments, theimplant is adapted to be allow for faster recovery and resumption ofnormal activities as compared to joint replacement therapy currentlymarketed.

In some embodiments, the balloon (or a portion thereof) is adapted toconform to the patient's anatomy. In some embodiments, the implant (or aportion thereof) is adapted to conform to the patient's anatomy. In someembodiments, the inflation medium is adapted to absorb a force (orforces) exerted on the joint. In some embodiments, the inflation mediumis adapted to absorb a force (or forces) exerted on the bones of thejoint. In some embodiments, the inflation medium is adapted to absorb aforce (or forces) exerted on at least one bone of the joint. In someembodiments, the balloon is adapted to absorb shocks exerted on at leastone of a bone, multiple bones, a ligament of the joint, ligaments of thejoint, a tendon of the joint, tendons of the joint, and the joint ingeneral. In some embodiments, the implant is adapted to restore naturalcartilage cushion with stem cells.

In some embodiments, the balloon (or a portion thereof) is adapted torenew joint space. In some embodiments, the balloon (or a portionthereof) is adapted to reducing pain as compared to the pain felt priorto the implantation of the implant. In some embodiments, the balloon (ora portion thereof) is adapted to restore joint function. In someembodiments, the implant (or a portion thereof) is adapted to renewjoint space. In some embodiments, the implant (or a portion thereof) isadapted to reducing pain as compared to the pain felt prior to theimplantation of the implant. In some embodiments, the implant (or aportion thereof) is adapted to restore joint function.

In some embodiments, the implant is adapted to reverse arthritis in thejoint.

In some embodiments, the balloon (or a portion thereof) is adapted to beplaced into a debrided limb joint arthroscopically. In some embodiments,the balloon is adapted to pad cartilage defects. In some embodiments,the balloon is inflated to cushion the joint. In some embodiments theimplant is adapted to deliver stem cells to at least one of the jointand a bone of the joint. In some embodiments the implant is adapted todeliver living chondrocytes to at least one of the joint and a bone ofthe joint. In some embodiments, the implant is adapted to provide a newarticular surface for the joint. In some embodiments, the implant isadapted to act as a spacer in the joint. In some embodiments, theimplant is adapted to space the bones of the joint apart for properjoint articulation. In some embodiments, the implant is adapted to spacethe bones of the joint apart for reduced bone-on-bone rubbing.

In some embodiments, the implant is configured to at least one of: padcartilage, cushion the joint, deliver a pharmacologic substance, removenoxious enzymes, debride upon implantation, debride the joint followingimplantation, deliver a therapeutic substance, deliver a biologicsubstance, and deliver living stem cells. In some embodiments, theimplant is configured to deliver a chemotherapeutic agent to a bone orother surrounding tissues. In some embodiments, the implant isconfigured to deliver an anti-infectious medication to a bone or othersurrounding tissues. In some embodiments, the implant is configured todeliver at least one of an antibiotic, antifungals, and analgesicsagent.

In some embodiments, the implant is configured to be selectivelyinflated to realign limbs.

Provided herein is a method comprising: implanting a knee implant asdescribed herein into a subject, wherein the implant reverses arthritisin the subject.

Provided herein is a method comprising: implanting a knee implant asdescribed herein into a knee joint of a subject and treating a componentof the knee joint of the subject with at least one of an allographtissue, an autograph tissue, and an xenograph tissue. In someembodiments, the implanting step is at least one of: prior to thetreating step, simultaneous with the treating step, and following thetreating step.

Provided herein is a method comprising: implanting a knee implant asdescribed herein into a subject, wherein the implant at least one of:restores joint function and controls arthopathies. In some embodiments,the implanting spares existing anatomy.

Provided herein is a method comprising: debriding a femur condyle of aknee joint of a subject, and implanting a knee implant as describedherein into the knee joint of the subject, whereby the implant isconfigured to anneal to the cartilage of the subject. In someembodiments, the debriding is achieved by steam application.

Provided herein is a method comprising implanting a knee implant asdescribed herein into a joint previously treated with a jointreplacement. In some embodiments, the method comprises removing thejoint replacement prior to implanting the knee implant. In someembodiments, the method comprises clearing infectious matter from thejoint and/or surrounding tissues. In some embodiments, the methodcomprises implanting a second implant of any implant described hereinfollowing removing the implant previously implanted in the joint. Insome embodiments, the method comprises replacing the joint of thesubject following removing the implant previously implanted in thejoint. In some embodiments, the method comprises debriding the bone ofthe joint, and implanting an implant of any implant described herein. Insome embodiments, the method comprises repeating the debriding andimplanting steps.

Additional Locations for Use

Shoulder subacromical bursa may be a target joint for an implant asdescribed herein. Rotator cuff tears may be addressed using an implantas described herein—as adjusted for the particular features, loadingprofile, and geometries of the joint. In shoulders, 85% of octagenianshave massive rotator cuff tears and often less than half normal upperextremity abduction and flexion capabilities. There may not besufficient remnant supraspinatus and other rotator cuff tissues to pulltogether. Then the humeral head rides up, in a cephalad direction,rubbing the superior bone surface on a frequently spurred and downwardsloping acromion. If a subacromial implant as described herein wereimplanted beneath the lateral (arthroscopically decompressed andprepared) acromion, the pain of bone on bone could be reduced, and thestructural anatomy between the ball and socket (humeral head and glenoidfossa) could be improved. In essence then a shoulder implant could coverthe humeral head analogous to the hip redundant membrane wherein thatmembrane replaces a normal subacromial bursa. Optionally, a singularbladder beneath the acromion per se could pad the ball beneath it. Forvirtually every joint in the body (arms and legs, at least) there aresimilar potential implant uses.

The distal femur of the knee, and the distal humerus of the elbow areregions that interface each with two opposite joints. That is, animplant for the knee as designed with polymer capping of the femoralcondyles and trochlear groove to provide cushioning of the femorotibialand patellafemoral joints. Analogously, in the humerus the distalcoverage enables padding restoration of the humeral-olecranon as well asthe radio-capitellar (part of the humerus) joint interfaces. Whereasgenerally the implant may cover the main or primary joint surface of thesurgeon's choice contributing to arthritis, consequently reducingsymptoms when treated, another alternative would be that the implant cancover any singular surface entirely or partially. It is generallydesired that the implant may cover one surface allowing remnantcartilages in other usually opposing or opposite surfaces to glideagainst the implant polymer with smooth gliding joint motion. Thisprinciple allows for retained joint linings or synovium to producelubricating substances including enzymes for facile joint movement. Italso avoids the wear debris that would accrue from polymer rubbing onpolymer, as recently recognized in metal on metal prostheses. In certainembodiments, the implant can cover more than one surface in a joint,such as the radiocapitallar joint wherein the distal humerus and theradial head receive prosthetic capping or interpositional application ofpolymers.

The surgical techniques may be individualized to fit patient need. Theimplants may be combined with or comprise autologous or allographtissues such as fascia lata. Surgeons may implant fascia lata aboveunreconstructable rotator cuff with consequent symptom relief. Polymerscan interface with any human tissue and/or with metals or polyethylenesor polyurethanes. Living tissues that can be combined with implantsprovided herein for repair or reconstruction may be from the samepatient (autograph), and cadaver or other member of the same species(allograph) or from another species (xenograph.) Virtually anycombination of polymer interpositioning is feasible with the implantconcepts provided herein, as anatomy varies among patients in need, andclinical conditions differ with each person. Therefore, although thegeneral or most common construct is expected to cover just one singularand the primary surface of a joint with an implant, any combination ofsurfaces can be involved allowing versatile custom applications of thisimplant and method of surgery.

Additionally, whereas implants as noted herein may be available inspecified sizes, the material membrane elastic deformation andresilience may allow for calculated malleability toward goodness of fit.In other iterations the fit of implant over the affected joint surfaceis customized as paring preoperative findings of MRI or CT or PETimaging pathophysiology with intraoperative reconstructive need.Ultimately best fit implants may serve patient restorative requirementwith least morbidity.

Locations wherein implants described herein may be additionally oralternatively applicable include all the limb joints of mammals. In theshoulder mainly the glenohumeral joint, though as discussed above thesubacromial space are useful loci for renewed padding whenpathophysiologies warrant. In the AC or acromioclavicular joint of theshoulder, a Mumford procedure (resection of the distal clavicle) can beavoided by inserted an implant as described herein. Even the TMJ in thejaw may be amenable to therapy using the implants noted herein.Proceeding distally in the aim, the elbow has two relevant jointsmentioned earlier, radiocapitellar and ulnohumeral. Depending on ‘wherethe arthritis forms’ (as from fracture or disease) the padding should berestored toward normal. Wrist, thumb and finger joints are many and mayrespond to vesicular implants with better durometry and vicsolubricantdelivery than tradition metal or silicon prostheses. Legs started at thehip joint have been shown via Hip implant prototypes to be amenable topolymer capping. Variations per surgeon's choice could evoke specialuses as for coverage of trochanteric bursae.

Additionally, the many functions of the implants noted herein may becoupled with cosmetic aspects in order to restore bulk and soft tissuebalance after scarring, injury or atrophy, or for purely cosmeticpurposes. Treatment for cosmesis especially when coupled with functionalor visual injury deficits can provide a reduction in physiological aswell as physical pain and discomfort. Therefore the extent minimallyinvasive implants restore the injured or diseased patient recipient tobecome hole, they are being used purposefully and as intended.

The knee joint is an initial focus of the figures wherein application tothe largest bone (the distal femur) accommodates padding needs for theopposing patella and tibia. The potential use of implants, however, overthe contralateral surfaces is an option that should not be ruled out. Inthe ankle the supratalar, or tibia talar joint will be a useful locationas may the subtalar area, depending on pathology present. Indicationsfor use may depend on the patients symptoms, from the history andphysical exam, based on studies such as roentgenograms, MRI or CTimaging, and may depend on test result from localized injections. Forexample, if a talus fracture pain were alleviated by sinus tarsiinjection then implant insertion into the subtalar joint would bepreferred. The talonavicular and other foot/toe joints are all amenableto renewed padding via an implant noted herein.

Pets, or other animals, such as cows, dogs, and horses, may be servedbetter by polymer joint capping than hip replacement for congenitaldysplasia. The successful treatment and rehabilitation of animals canfavorably affect the implant recipient and animal's owner, as pets canprovide functions necessary for activities of daily living (as a horsehelping to plow a field) or an animal relieved of pain from injury orarthritis can also be a comfort to its owner.

Kits

Provided herein are kits comprising multiple implants described herein.A kit may have implants as described herein as well as other implantsfor other parts of the body. A kit may comprise multiple sizes of asingle type of implant. A kit may comprise various implant types, suchas the patch, the unicompartment, and/or the dual compartment types ofimplants described herein. A kit may comprise various couplers, whichmay be selected by the surgeon depending on his comfort and expertise,and/or based on the particular patient anatomy and/or needs. The kit mayfurther comprise any insertion tools and/or surgery tools that mayuniquely assist in implanting the implant in the patient.

In addition to kits involving reparative implants, and insertionaltools, there may also be included software for translation of pre-injurydata and/or postoperative data collection and analysis, as well ascustom implants may be provided.

While particular forms of the invention have been illustrated anddescribed herein, it will be apparent that various modifications andimprovements can be made to the invention. One alternative implantconstruction involves the use of an upper portion of the implant havinga net-like construction and filled with balls or ball bearing likeelements that are larger than the openings in the netting. The balls orball bearing like elements provide motion to the implant. The nettingand ball bearing like elements may include regeneration agents aspreviously discussed, and the bearing construction may be directedtoward favorable implant movement balanced with content disbursement.

The invention is intended primarily for human use but may be extended tomammalian use. To the extent not otherwise disclosed herein, materialsand structure may be of conventional design.

Moreover, individual features of embodiments of the invention may beshown in some drawings and not in others, but those skilled in the artwill recognize that individual features of one embodiment of theinvention can be utilized in another embodiment. Moreover, individualfeatures of one embodiment may be combined with any or all the featuresof another embodiment. Accordingly, it is not intended that theinvention be limited to the specific embodiments illustrated. It istherefore intended that this invention be defined by the scope of theappended claims as broadly as the prior art will permit.

Terms such as “element”, “member”, “component”, “device”, “means”,“portion”, “section”, “steps” and words of similar import when usedherein shall not be construed as invoking the provisions of 35 U.S.C §112(6) unless the following claims expressly use the terms “means for”or “step for” followed by a particular function without reference to aspecific structure or a specific action. All patents and all patentapplications referred to above are hereby incorporated by reference intheir entirety.

While preferred embodiments of the present invention have been shown anddescribed herein, it will be obvious to those skilled in the art thatsuch embodiments are provided by way of example only. Numerousvariations, changes, and substitutions will now occur to those skilledin the art without departing from the invention. It should be understoodthat various alternatives to the embodiments of the invention describedherein may be employed in practicing the invention. It is intended thatthe following claims define the scope of the invention and that methodsand structures within the scope of these claims and their equivalents becovered thereby.

What is claimed is:
 1. A knee implant comprising: a first appendage thatis configured to engage a medial condyle of a femur of a knee joint, thefirst appendage comprising a bone engaging surface and an articulatingsurface, a second appendage that is configured to engage a lateralcondyle of a femur of a knee joint, the second appendage comprising abone engaging surface and an articulating surface, an average thickness,prefabricated holes for aiding in the attachment of the implant to abone, a slot between the first appendage and the second appendage, and arim defining the periphery of the implant, wherein the bone engagingsurface of the first appendage has a similar radial curvature profile asthe articulating surface of the first appendage.
 2. The knee implant ofclaim 1, wherein the average thickness of the implant of is from 0.05 to5 mm.
 3. The knee implant of claim 1, wherein the rim is a filleted rim.4. The knee implant of claim 1, wherein the filleted rim has a variablefillet.
 5. The implant of claim 1, wherein the implant is manufacturedfrom a thermoplastic polycarbonate urethane.
 6. The implant of claim 1,wherein the implant is a single polymeric layer of thermoplasticpolycarbonate urethane.
 7. The implant of claim 1, wherein the rim has adimension that is 1.0 to 3.5 times the thickness of the implant.
 8. Aknee implant comprising a first appendage that is configured to engage amedial condyle of a femur of a knee joint, the first appendagecomprising a bone engaging surface and an articulating surface, a secondappendage that is configured to engage a lateral condyle of a femur of aknee joint, the second appendage comprising a bone engaging surface andan articulating surface wherein after implanting the implant, thearticulating surfaces of both the first appendage and the secondappendage articulate relative to a patella, prefabricated holes foraiding in the attachment of the implant to a bone, an average thicknessthrough a main body of the implant of from 0.05 to 5 mm, a slot betweenthe first appendage and the second appendage, the main body of theimplant defined in its periphery by a rim, wherein the bone engagingsurface of the first appendage has a similar radial curvature profile asthe articulating surface of the first appendage.
 9. The knee implant ofclaim 8, wherein the rim is a filleted rim.
 10. The implant of claim 8,wherein the implant is manufactured from a thermoplastic polycarbonateurethane.
 11. The implant of claim 8, wherein the implant is a singlepolymeric layer of thermoplastic polycarbonate urethane.
 12. A kneeimplant comprising a first appendage that is configured to engage amedial condyle of a femur of a knee joint, the first appendagecomprising a bone engaging surface and an articulating surface, a secondappendage that is configured to engage a lateral condyle of a femur of aknee joint, the second appendage comprising a bone engaging surface andan articulating surface wherein once implanted the articulating surfacearticulates relative to at least one ligament, prefabricated holes foraiding in the attachment of the implant to a bone, an average thicknessthrough a main body of the implant of from 0.05 to 5 mm, a slot betweenthe first appendage and the second appendage, the main body of theimplant defined in its periphery by a filleted rim, wherein the boneengaging surface of the first appendage has a similar radial curvatureprofile as the articulating surface of the first appendage.
 13. Theimplant of claim 12, wherein the implant is manufactured from athermoplastic polycarbonate urethane.
 14. The implant of claim 12,wherein the implant is a single polymeric layer of thermoplasticpolycarbonate urethane.